The rationale is that it's broken at least on some platforms (e.g.
TextureHost::GetAsSurface() is not implemented), and moving it under its own
environment variable allows us to use the client-side parts of paint dumping
without crashing while attempting to do the compositor-side parts.
The bulk of this commit was generated by running:
run-clang-tidy.py \
-checks='-*,llvm-namespace-comment' \
-header-filter=^/.../mozilla-central/.* \
-fix
For frame statistics to work properly, we have to notify an ImageContainer
when it has been composited. This requires a few changes, which have
been lumped together in this patch:
-- Create PImageContainer and ImageContainerParent/ImageContainerChild.
-- Add mFrameID and mProducerID everywhere we're passing around images.
-- Route composition notifications from the compositor back to
ImageContainerChild.
