* Fix crash during server render.
setTimeout and clearTimeout may not be available in some server-render environments (such as ChakraCore in React.NET), and loading ReactScheduler.js will cause a crash unless the existence of the variables are checked via a typeof comparison.
https://github.com/reactjs/React.NET/issues/555
The crash did not occur in 16.4.0, and the change appears to have been introduced here: https://github.com/facebook/react/pull/12931/files#diff-bbebc3357e1fb99ab13ad796e04b69a6L47
I tested this by using yarn link and running it with a local copy of React.NET. I am unsure the best way to unit test this change, since assigning null to `setTimeout` causes an immediate crash within the Node REPL.
* Fix flow errors and log warning if setTimeout / clearTimeout are
not defined / not a function.
* Use invariant to assert setTimeout / clearTimeout are functions
* Remove use of invariant
* Explain
* Add fixture test for schedule running when tab is backgrounded
**what is the change?:**
Just adding a test to the fixture, where we can easily see whether
scheduled callbacks are called after switching away from the fixture
tab.
**why make this change?:**
We are about to fix the schedule module so that it still runs even when
the tab is in the backround.
**test plan:**
Manually tested the fixture, verified that it works as expected and
right now callbacks are not called when the tab is in the background.
**issue:**
Internal task T30754186
* Fall back to 'setTimeout' when 'requestAnimationFrame' is not called
**what is the change?:**
If 'requestAnimationFrame' is not called for 100ms we fall back to
'setTimeout' to schedule the postmessage.
**why make this change?:**
When you start loading a page, and then switch tabs,
'requestAnimationFrame' is throttled or not called until you come back
to that tab. That means React's rendering, any any other scheduled work,
are paused.
Users expect the page to continue loading, and rendering is part of the
page load in a React app. So we need to continue calling callbacks.
**test plan:**
Manually tested using the new fixture test, observed that the callbacks
were called while switched to another tab. They were called more
slowly, but that seems like a reasonable thing.
**issue:**
Internal task T30754186
* make arguments more explicit
* Remove rAF fork
**what is the change?:**
Undid https://github.com/facebook/react/pull/12837
**why make this change?:**
We originally forked rAF because we needed to pull in a particular
version of rAF internally at Facebook, to avoid grabbing the default
polyfilled version.
The longer term solution, until we can get rid of the global polyfill
behavior, is to initialize 'schedule' before the polyfilling happens.
Now that we have landed and synced
https://github.com/facebook/react/pull/12900 successfully, we can
initialize 'schedule' before the polyfill runs.
So we can remove the rAF fork. Here is how it will work:
1. Land this PR on Github.
2. Flarnie will quickly run a sync getting this change into www.
3. We delete the internal forked version of
'requestAnimationFrameForReact'.
4. We require 'schedule' in the polyfill file itself, before the
polyfilling happens.
**test plan:**
Flarnie will manually try the above steps locally and verify that things
work.
**issue:**
Internal task T29442940
* fix nits
* fix tests, fix changes from rebasing
* fix lint
* Use native event dispatching instead of Simulate or SimulateNative
In #12629 @gaearon suggested that it would be better to drop usage of
`ReactTestUtils.Simulate` and `ReactTestUtils.SimulateNative`. In this
PR I’m attempting at removing it from a lot of places with only a few
leftovers.
Those leftovers can be categorized into three groups:
1. Anything that tests that `SimulateNative` throws. This is a property
that native event dispatching doesn’t have so I can’t convert that
easily. Affected test suites: `EventPluginHub-test`,
`ReactBrowserEventEmitter-test`.
2. Anything that tests `ReactTestUtils` directly. Affected test suites:
`ReactBrowserEventEmitter-test` (this file has one test that reads
"should have mouse enter simulated by test utils"),
`ReactTestUtils-test`.
3. Anything that dispatches a `change` event. The reason here goes a bit
deeper and is rooted in the way we shim onChange. Usually when using
native event dispatching, you would set the node’s `.value` and then
dispatch the event. However inside [`inputValueTracking.js`][] we
install a setter on the node’s `.value` that will ignore the next
`change` event (I found [this][near-perfect-oninput-shim] article
from Sophie that explains that this is to avoid onChange when
updating the value via JavaScript).
All remaining usages of `Simulate` or `SimulateNative` can be avoided
by mounting the containers inside the `document` and dispatching native
events.
Here some remarks:
1. I’m using `Element#click()` instead of `dispatchEvent`. In the jsdom
changelog I read that `click()` now properly sets the correct values
(you can also verify it does the same thing by looking at the
[source][jsdom-source]).
2. I had to update jsdom in order to get `TouchEvent` constructors
working (and while doing so also updated jest). There was one
unexpected surprise: `ReactScheduler-test` was relying on not having
`window.performance` available. I’ve recreated the previous
environment by deleting this property from the global object.
3. I was a bit confused that `ReactTestUtils.renderIntoDocument()` does
not render into the document 🤷
[`inputValueTracking.js`]: https://github.com/facebook/react/blob/392530104c00c25074ce38e1f7e1dd363018c7ce/packages/react-dom/src/client/inputValueTracking.js#L79
[near-perfect-oninput-shim]: https://sophiebits.com/2013/06/18/a-near-perfect-oninput-shim-for-ie-8-and-9.html
[jsdom-source]: https://github.com/jsdom/jsdom/blob/45b77f5d21cef74cad278d089937d8462c29acce/lib/jsdom/living/nodes/HTMLElement-impl.js#L43-L76
* Make sure contains are unlinked from the document even if the test fails
* Remove unnecessary findDOMNode calls
* Fix react-dom ReferenceError requestAnimationFrame in non-browser env (#13000)
The https://github.com/facebook/react/pull/12931 ( https://github.com/facebook/react/commit/79a740c6e32ca300d4e7ff55ab06de172d4237fd ) broke the server-side rendering: in the `fixtures/ssr` the following error appeared from the server-side when `localhost:3000` is requested:
```
ReferenceError: requestAnimationFrame is not defined
at /__CENSORED__/react/build/node_modules/react-dom/cjs/react-dom.development.js:5232:34
at Object.<anonymous> (/__CENSORED__/react/build/node_modules/react-dom/cjs/react-dom.development.js:17632:5)
at Module._compile (module.js:624:30)
at Module._extensions..js (module.js:635:10)
at Object.require.extensions.(anonymous function) [as .js] (/__CENSORED__/react/fixtures/ssr/node_modules/babel-register/lib/node.js:152:7)
at Module.load (module.js:545:32)
at tryModuleLoad (module.js:508:12)
at Function.Module._load (module.js:500:3)
at Module.require (module.js:568:17)
at require (internal/module.js:11:18)
```
The exception pointed to this line:
```js
// We capture a local reference to any global, in case it gets polyfilled after
// this module is initially evaluated.
// We want to be using a consistent implementation.
const localRequestAnimationFrame = requestAnimationFrame;
```
**Test plan**
1. In `react` repo root, `yarn && yarn build`.
2. In `fixtures/ssr`, `yarn && yarn start`,
3. In browser, go to `http://localhost:3000`.
4. Observe the fixture page, not the exception message.
* Move the requestAnimationFrameForReact check and warning to callsites (#13000)
According to the comment by @gaearon: https://github.com/facebook/react/pull/13001#issuecomment-395803076
* Use `invariant` instead of `throw new Error`, use the same message (#13000)
According to the comment by @gaearon: https://github.com/facebook/react/pull/13001#discussion_r194133355
* Initial failing unit test for error handling in schedule
**what is the change?:**
see title
**why make this change?:**
Adding tests for the error handling behavior we are about to add. This
test is failing, which gives us the chance to make it pass.
Wrote skeletons of some other tests to add.
Unit testing this way is really hacky, and I'm also adding to the
fixture to test this in the real browser environment.
**test plan:**
Ran new test, saw it fail!
* Add fixture for testing error handling in scheduler
**what is the change?:**
Added a fixture which does the following -
logs in the console to show what happens when you use
`requestAnimationFrame` to schedule a series of callbacks and some of
them throw errors.
Then does the same actions with the `scheduler` and verifies that it
behaves in a similar way.
Hard to really verify the errors get thrown at the proper time without
looking at the console.
**why make this change?:**
We want the most authentic, accurate test of how errors are handled in
the scheduler. That's what this fixture should be.
**test plan:**
Manually verified that this test does what I expect - right now it's
failing but follow up commits will fix that.
* Handle errors in scheduler
**what is the change?:**
We set a flag before calling any callback, and then use a 'try/finally'
block to wrap it. Note that we *do not* catch the error, if one is
thrown. But, we only unset the flag after the callback successfully
finishes.
If we reach the 'finally' block and the flag was not unset, then it
means an error was thrown.
In that case we start a new postMessage callback, to finish calling any
other pending callbacks if there is time.
**why make this change?:**
We need to make sure that an error thrown from one callback doesn't stop
other callbacks from firing, but we also don't want to catch or swallow
the error because we want engineers to still be able to log and debug
errors.
**test plan:**
New tests added are passing, and we verified that they fail without this
change.
* Add more tests for error handling in scheduler
**what is the change?:**
Added tests for more situations where error handling may come up.
**why make this change?:**
To get additional protection against this being broken in the future.
**test plan:**
Ran new tests and verified that they fail when error handling fails.
* callSafely -> callUnsafely
* Fix bugs with error handling in schedule
**what is the change?:**
- ensure that we properly remove the callback from the linked list, even
if it throws an error and is timed out.
- ensure that you can call 'cancelScheduledWork' more than once and it
is idempotent.
**why make this change?:**
To fix bugs :)
**test plan:**
Existing tests pass, and we'll add more tests in a follow up commit.
* Unit tests for error handling with timed out callbacks
**what is the change?:**
More unit tests, to cover behavior which we missed; error handling of
timed out callbacks.
**why make this change?:**
To protect the future!~
**test plan:**
Run the new tests.
* Adds fixture to test timed out callbacks with scheduler
**what is the change?:**
See title
In the other error handling fixture we compare 'scheduleWork' error
handling to 'requestAnimationFrame' and try to get as close as possible.
There is no 'timing out' feature with 'requestAnimationFrame' but
effectively the 'timing out' feature changes the order in which things
are called. So we just changed the order in the 'requestAnimationFrame'
version and that works well for illustrating the behavior we expect in
the 'scheduleWork' test.
**why make this change?:**
We need more test coverage of timed out callbacks.
**test plan:**
Executed the fixture manually in Firefox and Chrome. Results looked
good.
* fix rebase problems
* make fixture compensate for chrome JS speed
* ran prettier
* Remove 'cancelled' flag on callbackConfig in scheduler, add test
**what is the change?:**
- Instead of using a 'cancelled' flag on the callbackConfig, it's easier
to just check the state of the callbackConfig inside
'cancelScheduledWork' to determine if it's already been cancelled. That
way we don't have to remember to set the 'cancelled' flag every time we
call a callback or cancel it. One less thing to remember.
- We added a test for calling 'cancelScheduledWork' more than once,
which would have failed before.
Thanks @acdlite for suggesting this in code review. :)
**why make this change?:**
To increase stability of the schedule module, increase test coverage.
**test plan:**
Existing tests pass and we added a new test to cover this behavior.
* fix typo
**what is the change?:**
In a recent PR we were referencing some global variables and storing
local references to them.
To make things more natural, we co-opted the original name of the global
for our local reference. To make this work with Flow, we get the
original reference from 'window.requestAnimationFrame' and assign it to
'const requestAnimationFrame'.
Sometimes React is used in an environment where 'window' is not defined
- in that case we need to use something else, or hide the 'window'
reference somewhere.
We opted to use 'global' thinking that Babel transforms would fill that
in with the proper thing.
But for some of our fixtures we are not doing that transform on the
bundle.
**why make this change?:**
I want to unbreak this on master and then investigate more about what we
should do to fix this.
**test plan:**
run `yarn build` and open the fixtures.
**issue:**
https://github.com/facebook/react/issues/12930
* Use local references to global things inside 'scheduler'
**what is the change?:**
See title
**why make this change?:**
We want to avoid initially calling one version of an API and then later
accessing a polyfilled version.
**test plan:**
Run existing tests.
* Shim ReactScheduler for www
**what is the change?:**
In 'www' we want to reference the separate build of ReactScheduler,
which allows treating it as a separate module internally.
**why make this change?:**
We need to require the ReactScheduler before our rAF polyfill activates,
in order to customize which custom behaviors we want.
This is also a step towards being able to experiment with using it
outside of React.
**test plan:**
Ran tests, ran the build, and ran `test-build`.
* Generate a bundle for fb-www
**what is the change?:**
See title
**why make this change?:**
Splitting out the 'schedule' module allows us to load it before
polyfills kick in for rAF and other APIs.
And long term we want to split this into a separate module anyway, this
is a step towards that.
**test plan:**
I'll run the sync next week and verify that this all works. :)
* ran prettier
* fix rebase issues
* Change names of variables used for holding globals
* [schedule] Use linked list instead of queue and map for storing cbs
NOTE: This PR depends on https://github.com/facebook/react/pull/12880
and https://github.com/facebook/react/pull/12884
Please review those first, and after they land Flarnie will rebase on
top of them.
---
**what is the change?:**
See title
**why make this change?:**
This seems to make the code simpler, and potentially saves space of
having an array and object around holding references to the callbacks.
**test plan:**
Run existing tests
* minor style improvements
* refactor conditionals in cancelScheduledWork for increased clarity
* Remove 'canUseDOM' condition and fix some flow issues w/callbackID type
**what is the change?:**
- Removed conditional which fell back to 'setTimeout' when the
environment doesn't have DOM. This appears to be an old polyfill used
for test environments and we don't use it any more.
- Fixed type definitions around the callbackID to be more accurate in
the scheduler itself, and more loose in the React code.
**why make this change?:**
To get Flow passing, simplify the scheduler code, make things accurate.
**test plan:**
Run tests and flow.
* Rewrite 'cancelScheduledWork' so that Flow accepts it
**what is the change?:**
Adding verification that 'previousCallbackConfig' and
'nextCallbackConfig' are not null before accessing properties on them.
Slightly concerned because this implementation relies on these
properties being untouched and correct on the config which is passed to
'cancelScheduledWork' but I guess we already rely heavily on that for
this whole approach. :\
**why make this change?:**
To get Flow passing.
Not sure why it passed earlier and in CI, but now it's not.
**test plan:**
`yarn flow dom` and other flow tests, lint, tests, etc.
* ran prettier
* Put back the fallback implementation of scheduler for node environment
**what is the change?:**
We had tried removing the fallback implementation of `scheduler` but
tests reminded us that this is important for supporting isomorphic uses
of React.
Long term we will move this out of the `schedule` module but for now
let's keep things simple.
**why make this change?:**
Keep things working!
**test plan:**
Ran tests and flow
* Shorten properties stored in objects by sheduler
**what is the change?:**
`previousScheduledCallback` -> `prev`
`nextScheduledCallback` -> `next`
**why make this change?:**
We want this package to be smaller, and less letters means less code
means smaller!
**test plan:**
ran existing tests
* further remove extra lines in scheduler
* Adding 'schedule' fixture
**what is the change?:**
We need to test the `schedule` module against real live browser APIs. As
a quick solution we're writing a fixture for using in manual testing.
Later we plan on adding automated browser testing, using this or a
similar fixture as the test page.
**why make this change?:**
To further solidify test coverage for `schedule` before making further
improvements/refactors to the module.
**test plan:**
`open fixtures/schedule/index.html` and inspect the results. It should
be clear that things pass.
We also temporarily broke the scheduler and verified that this fixture
demonstrates the problems.
**issue:**
Internal task T29442940
* Made fixture tests display red or green border depending on pass/fail
**what is the change?:**
Added red/green solid/dashed border for test results when using the
schedule fixture.
We also tweaked the timing of the last test because it was on the line
in terms of whether it passed or failed.
**why make this change?:**
To make it faster to use the fixture - it takes more time to read
through the results line by line and check that they match what is
expected.
**test plan:**
Looked at the fixture, and also tried modifying a test to show what it
looks like when something fails.
**what is the change?:**
Renamed some methods, and made a method to advance a frame in the test
environment.
**why make this change?:**
We often need to simulate a frame passing with some amount of idle time
or lack of idle time, and the new method makes it easier to write that
out.
**test plan:**
Run the updated tests.
Also temporarily tried breaking the scheduler and verified that the
tests will fail.
**issue:**
See internal task T29442940
**what is the change?:**
Test coverage checking that callbacks are called when they time out.
This test surfaced a bug and this commit includes the fix.
I want to refine this approach, but basically we can simulate time outs
by controlling the return value of 'now()' and the argument passed to
the rAF callback.
Next we will write a browser fixture to further test this against real
browser APIs.
**why make this change?:**
Better tests will keep this module working smoothly while we continue
refactoring and improving it.
**test plan:**
Run the new tests, see that it fails without the bug fix.
* Extract base Jest config
This makes it easier to change the source config without affecting the build test config.
* Statically import the host config
This changes react-reconciler to import HostConfig instead of getting it through a function argument.
Rather than start with packages like ReactDOM that want to inline it, I started with React Noop and ensured that *custom* renderers using react-reconciler package still work. To do this, I'm making HostConfig module in the reconciler look at a global variable by default (which, in case of the react-reconciler npm package, ends up being the host config argument in the top-level scope).
This is still very broken.
* Add scaffolding for importing an inlined renderer
* Fix the build
* ES exports for renderer methods
* ES modules for host configs
* Remove closures from the reconciler
* Check each renderer's config with Flow
* Fix uncovered Flow issue
We know nextHydratableInstance doesn't get mutated inside this function, but Flow doesn't so it thinks it may be null.
Help Flow.
* Prettier
* Get rid of enable*Reconciler flags
They are not as useful anymore because for almost all cases (except third party renderers) we *know* whether it supports mutation or persistence.
This refactoring means react-reconciler and react-reconciler/persistent third-party packages now ship the same thing.
Not ideal, but this seems worth how simpler the code becomes. We can later look into addressing it by having a single toggle instead.
* Prettier again
* Fix Flow config creation issue
* Fix imprecise Flow typing
* Revert accidental changes
**what is the change?:**
Fix a typo which caused timed out callbacks to not be called.
**why make this change?:**
This is a bug caught by tests I'm in the process of writing, and we
should fix it asap.
**test plan:**
Tests in a WIP PR - will push and share the WIP test in comments on this
PR.
* Temporary fix for grabbing wrong rAF polyfill in ReactScheduler
**what is the change?:**
For now...
We need to grab a slightly different implementation of rAF internally at
FB than in Open Source. Making rAF a dependency of the ReactScheduler
module allows us to fork the dependency at FB.
NOTE: After this lands we have an alternative plan to make this module
separate from React and require it before our Facebook timer polyfills
are applied. But want to land this now to keep master in a working state
and fix bugs folks are seeing at Facebook.
Thanks @sebmarkbage @acdlite and @sophiebits for discussing the options
and trade-offs for solving this issue.
**why make this change?:**
This fixes a problem we're running into when experimenting with
ReactScheduler internally at Facebook, **and* it's part of our long term
plan to use dependency injection with the scheduler to make it easier to
test and adjust.
**test plan:**
Ran tests, lint, flow, and will manually test when syncing into
Facebook's codebase.
**issue:**
See internal task T29442940
* ran prettier
**what is the change?:**
We were setting a flag after some early returns, should have set it
right away.
To be fair, it's not clear how you can hit a problem with the current
state of things. Even if a callback is cancelled, it's still in the
'pendingCallbacks' queue until the rAF runs, and we only schedule a rAF
when there are pendingCallbacks in the queue.
But since this is obviously wrong, going to fix it.
We will be adding a regression test in a follow-up PR.
**why make this change?:**
To fix a random bug which was popping up.
**test plan:**
Adding a regression unit test in a follow-up PR.
**what is the change?:**
In some cases we had defined the 'callback' as taking two arguments,
when really we meant to indicate the second argument passed to
'scheduleWork'.
**why make this change?:**
For correctness and to unblock something @gaearon is working on. A bit
surprised Flow didn't catch this in the first place.
**test plan:**
Ran tests, flow, lint.
* Rename Scheduler methods more accurately
**what is the change?:**
```
rIC -> scheduleCallback
```
We will later expose a second method for different priority level, name
TBD. Since we only have one priority right now we can delay the
bikeshedding about the priority names.
cIC -> cancelScheduledCallback
This method can be used to cancel callbacks scheduled at any priority
level, and will remain named this way.
why make this change?:
Originally this module contained a polyfill for requestIdleCallback
and cancelIdleCallback but we are changing the behavior so it's no
longer just a polyfill. The new names are more semantic and distinguish
this from the original polyfill functionality.
**test plan:**
Ran the tests
**why make this change?:**
Getting this out of the way so things are more clear.
**Coming Up Next:**
- Switching from a Map of ids and an array to a linked list for storing
callbacks.
- Error handling
* callback -> work
* update callsites in new places after rebase
* fix typo
* Support using id to cancel scheduled callback
**what is the change?:**
see title
**why make this change?:**
Once we support multiple callbacks you will need to use the id to
specify which callback you mean.
**test plan:**
Added a test, ran all tests, lint, etc.
* ran prettier
* fix lint
* Use object for storing callback info in scheduler
* Wrap initial test in a describe block
* Support multiple callbacks in `ReactScheduler`
**what is the change?:**
We keep a queue of callbacks instead of just one at a time, and call
them in order first by their timeoutTime and then by the order which
they were scheduled in.
**why make this change?:**
We plan on using this module to coordinate JS outside of React, so we
will need to schedule more than one callback at a time.
**test plan:**
Added a boatload of shiny new tests. :)
Plus ran all the old ones.
NOTE: The tests do not yet cover the vital logic of callbacks timing
out, and later commits will add the missing test coverage.
* Heuristic to avoid looking for timed out callbacks when none timed out
**what is the change?:**
Tracks the current soonest timeOut time for all scheduled callbacks.
**why make this change?:**
We were checking every scheduled callback to see if it timed out on
every tick. It's more efficient to skip that O(n) check if we know that
none have timed out.
**test plan:**
Ran existing tests.
Will write new tests to cover timeout behavior in more detail soon.
* Put multiple callback support under a disabled feature flag
**what is the change?:**
See title
**why make this change?:**
We don't have error handling in place yet, so should maintain the old
behavior until that is in place.
But want to get this far to continue making incremental changes.
**test plan:**
Updated and ran tests.
* Hide support for multiple callbacks under a feature flag
**what is the change?:**
see title
**why make this change?:**
We haven't added error handling yet, so should not expose this feature.
**test plan:**
Ran all tests, temporarily split out the tests for multiple callbacks
into separate file. Will recombine once we remove the flag.
* Fix nits from code review
See comments on https://github.com/facebook/react/pull/12743
* update checklist in comments
* Remove nested loop which calls additional timed out callbacks
**what is the change?:**
We used to re-run any callbacks which time out whilst other callbacks
are running, but now we will only check once for timed out callbacks
then then run them.
**why make this change?:**
To simplify the code and the behavior of this module.
**test plan:**
Ran all existing tests.
* Remove feature flag
**what is the change?:**
see title
**why make this change?:**
Because only React is using this, and it sounds like async. rendering
won't hit any different behavior due to these changes.
**test plan:**
Existing tests pass, and this allowed us to recombine all tests to run
in both 'test' and 'test-build' modes.
* remove outdated file
* fix typo
**what is the change?:**
We had a condition to set either 'performance.now' or 'Date.now' as the
'now' function.
Then later we had another conditional checking again if
'performance.now' was supported, and using it if so, otherwise falling
back to 'Date.now'.
More efficient to just use the 'now' shortcut defined above.
**why make this change?:**
Fewer lines, clearer code.
**test plan:**
Now that we have tests we can run them :)
* Remove the 'alwaysUseRequestIdleCallbackPolyfill' feature flag
**what is the change?:**
Removes the feature flag 'alwaysUseRequestIdleCallbackPolyfill', such
that we **always** use the polyfill for requestIdleCallback.
**why make this change?:**
We have been testing this feature flag at 100% for some time internally,
and determined it works better for React than the native implementation.
Looks like RN was overriding the flag to use the native when possible,
but since no RN products are using 'async' mode it should be safe to
switch this flag over for RN as well.
**test plan:**
We have already been testing this internally for some time.
**issue:**
internal task t28128480
* fix mistaken conditional
* Add mocking of rAF, postMessage, and initial test for ReactScheduler
**what is the change?:**
- In all tests where we previously mocked rIC or relied on native
mocking which no longer works, we are now mocking rAF and postMessage.
- Also adds a basic initial test for ReactScheduler.
NOTE -> we do plan to write headless browser tests for ReactScheduler!
This is just an initial test, to verify that it works with the mocked
out browser APIs as expected.
**why make this change?:**
We need to mock out the browser APIs more completely for the new
'ReactScheduler' to work in our tests. Many tests are depending on it,
since it's used at a low level.
By mocking the browser APIs rather than the 'react-scheduler' module, we
enable testing the production bundles. This approach is trading
isolation for accuracy. These tests will be closer to a real use.
**test plan:**
run the tests :)
**issue:**
internal task T28128480
This is the first step - pulling the ReactDOMFrameScheduling module out
into a separate package.
Co-authored-by: Brandon Dail <aweary@users.noreply.github.com>