Don't remove CodecImages from the wrong CodecImageGroup.

MaybeRenderEarlyManager tried to remove images from the wrong codec
group in some cases, leaving the right group with a raw pointer to
the CodecImage, and no way to remove it.

This can be simplified, but this is a small text change to permit
merge back to beta.

Bug: 986783
Change-Id: I3643cd0b847250157b0ce2162c176f0113975bec
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1801330Reviewed-by: Dan Sanders <sandersd@chromium.org>
Reviewed-by: Dale Curtis <dalecurtis@chromium.org>
Commit-Queue: Frank Liberato <liberato@chromium.org>
Cr-Commit-Position: refs/heads/master@{#696146}

media/gpu/android/maybe_render_early_manager.cc

@@ -51,7 +51,13 @@ class GpuMaybeRenderEarlyImpl {
     // adding a DestructionCB to CodecImage.  However, since we use a weak ptr
     // for the callback, it isn't safe.  CodecImageGroup uses a strong ref.
     DCHECK(std::find(images_.begin(), images_.end(), image) != images_.end());
-    image_group_->RemoveCodecImage(image);
+    // Remember that |image_group_| might not be the same one that |image|
+    // belongs to.  So, we can't remove it.  Instead, trust that the destruction
+    // cb will also be run.
+    // TODO(liberato): Simplify this.  We don't need both callbacks.  The
+    // destruction CB can be renamed to the unused cb, and CodecImageGroup can
+    // set it like it used to, and notify us about it.  It would be called both
+    // on CodecImage destruction and (with pooling) when it's unused.
     base::Erase(images_, image);
     internal::MaybeRenderEarly(&images_);
   }