Remove references to Deletion flag (#20623)

We no longer use the Deletion flag anywhere in the new fork, so we can
stop marking it.

packages/react-reconciler/src/ReactChildFiber.new.js

@@ -13,12 +13,7 @@ import type {Fiber} from './ReactInternalTypes';
 import type {Lanes} from './ReactFiberLane.new';
 
 import getComponentName from 'shared/getComponentName';
-import {
-  Deletion,
-  ChildDeletion,
-  Placement,
-  StaticMask,
-} from './ReactFiberFlags';
+import {Placement, ChildDeletion} from './ReactFiberFlags';
 import {
   getIteratorFn,
   REACT_ELEMENT_TYPE,
@@ -281,7 +276,6 @@ function ChildReconciler(shouldTrackSideEffects) {
       returnFiber.firstEffect = returnFiber.lastEffect = childToDelete;
     }
     childToDelete.nextEffect = null;
-    childToDelete.flags = (childToDelete.flags & StaticMask) | Deletion;
 
     const deletions = returnFiber.deletions;
     if (deletions === null) {

packages/react-reconciler/src/ReactFiberBeginWork.new.js

@@ -67,7 +67,6 @@ import {
   DidCapture,
   Update,
   Ref,
-  Deletion,
   ChildDeletion,
   ForceUpdateForLegacySuspense,
   StaticMask,
@@ -2200,8 +2199,6 @@ function updateSuspensePrimaryChildren(
   if (currentFallbackChildFragment !== null) {
     // Delete the fallback child fragment
     currentFallbackChildFragment.nextEffect = null;
-    currentFallbackChildFragment.flags =
-      (currentFallbackChildFragment.flags & StaticMask) | Deletion;
     workInProgress.firstEffect = workInProgress.lastEffect = currentFallbackChildFragment;
     const deletions = workInProgress.deletions;
     if (deletions === null) {
@@ -3191,7 +3188,6 @@ function remountFiber(
       returnFiber.firstEffect = returnFiber.lastEffect = current;
     }
     current.nextEffect = null;
-    current.flags = (current.flags & StaticMask) | Deletion;
 
     const deletions = returnFiber.deletions;
     if (deletions === null) {

packages/react-reconciler/src/ReactFiberHydrationContext.new.js

@@ -24,13 +24,7 @@ import {
   HostRoot,
   SuspenseComponent,
 } from './ReactWorkTags';
-import {
-  Deletion,
-  ChildDeletion,
-  Placement,
-  Hydrating,
-  StaticMask,
-} from './ReactFiberFlags';
+import {ChildDeletion, Placement, Hydrating} from './ReactFiberFlags';
 import invariant from 'shared/invariant';
 
 import {
@@ -130,7 +124,6 @@ function deleteHydratableInstance(
   const childToDelete = createFiberFromHostInstanceForDeletion();
   childToDelete.stateNode = instance;
   childToDelete.return = returnFiber;
-  childToDelete.flags = (childToDelete.flags & StaticMask) | Deletion;
 
   // This might seem like it belongs on progressedFirstDeletion. However,
   // these children are not part of the reconciliation list of children.