[Flight] Fix pending chunks count for streams & async iterables in DEV (facebook#35143)

In DEV, we need to prevent the response from being GC'd while there are
still pending chunks for ReadableSteams or pending results for
AsyncIterables.

Co-authored-by: Sebastian "Sebbie" Silbermann <[email protected]>

Author: unstubbable

packages/react-client/src/ReactFlightClient.js

@@ -813,6 +813,12 @@ function createInitializedStreamChunk<
   value: T,
   controller: FlightStreamController,
 ): InitializedChunk<T> {
+  if (__DEV__) {
+    // Retain a strong reference to the Response while we wait for chunks.
+    if (response._pendingChunks++ === 0) {
+      response._weakResponse.response = response;
+    }
+  }
   // We use the reason field to stash the controller since we already have that
   // field. It's a bit of a hack but efficient.
   // $FlowFixMe[invalid-constructor] Flow doesn't support functions as constructors
@@ -3075,7 +3081,6 @@ function resolveStream<T: ReadableStream | $AsyncIterable<any, any, void>>(
     // We already resolved. We didn't expect to see this.
     return;
   }
-  releasePendingChunk(response, chunk);
 
   const resolveListeners = chunk.value;
 
@@ -3375,6 +3380,14 @@ function stopStream(
     // We didn't expect not to have an existing stream;
     return;
   }
+  if (__DEV__) {
+    if (--response._pendingChunks === 0) {
+      // We're no longer waiting for any more chunks. We can release the strong
+      // reference to the response. We'll regain it if we ask for any more data
+      // later on.
+      response._weakResponse.response = null;
+    }
+  }
   const streamChunk: InitializedStreamChunk<any> = (chunk: any);
   const controller = streamChunk.reason;
   controller.close(row === '' ? '"$undefined"' : row);