InferReferenceEffects: distinguish conditional mutations in HIR

In InferReferenceEffects, locations that are ConditionallyMutate are either 
recorded as a Mutate or Read, which means we lose the distinction btw 
conditional/unconditional mutation in later passes. This PR changes to remember 
that these places were conditionally mutable, used in later analysis.

compiler/forget/packages/babel-plugin-react-forget/src/HIR/HIR.ts

@@ -878,16 +878,11 @@ export function isMutableEffect(
   switch (effect) {
     case Effect.Capture:
     case Effect.Store:
+    case Effect.ConditionallyMutate:
     case Effect.Mutate: {
       return true;
     }
-    case Effect.ConditionallyMutate: {
-      // All conditional mutations should be resolved into some other effect after InferReferenceEffects
-      CompilerError.invariant(
-        "Unexpected conditional mutation effect",
-        location
-      );
-    }
+
     case Effect.Unknown: {
       CompilerError.invariant("Unexpected unknown effect", location);
     }

compiler/forget/packages/babel-plugin-react-forget/src/Inference/InferReferenceEffects.ts

@@ -311,7 +311,7 @@ class InferenceState {
           valueKind === ValueKind.Mutable ||
           valueKind === ValueKind.Context
         ) {
-          effect = Effect.Mutate;
+          effect = Effect.ConditionallyMutate;
         } else {
           effect = Effect.Read;
         }

compiler/forget/packages/babel-plugin-react-forget/src/__tests__/fixtures/compiler/error.invalid-pass-ref-to-function.expect.md

@@ -14,7 +14,7 @@ function Component(props) {
 ## Error
 
 ```
-[ReactForget] InvalidInput: Ref values may not be passed to functions because they could read the ref value (`current` property) during render. Cannot access ref object at mutate $22[6:8]:TObject<BuiltInUseRefId> (3:3)
+[ReactForget] InvalidInput: Ref values may not be passed to functions because they could read the ref value (`current` property) during render. Cannot access ref object at mutate? $22[6:8]:TObject<BuiltInUseRefId> (3:3)
 ```