Revert of Discard compositor frames from unloaded web content (patchset #11 id:200001 of https://codereview.chromium.org/2707243005/ )

Reason for revert:
It looks like this broke the MSAN bot:

https://uberchromegw.corp.google.com/i/chromium.webkit/builders/WebKit%20Linux%20Trusty%20MSAN

https://uberchromegw.corp.google.com/i/chromium.webkit/builders/WebKit%20Linux%20Trusty%20MSAN/builds/731

Original issue's description:
> Discard compositor frames from unloaded web content
>
> After a navigation commits, it is still possible for the compositor to
> resend a frame that draws the previous (now unloaded) page. In some
> situations this works against the browser process' new content
> rendering timer that attempts to clear a page after 4 seconds if a
> navigation has committed but not yet painted in that time.
>
> This CL adds a counter called content_source_id to that increments on
> every non-same-page navigation commit under a given top-level
> RenderWidget. It tags the CompositorFrameMetadata with this identifier,
> and also sends it to the browser process with the
> DidCommitProvisionaLoad IPC message. This enables the browser to
> recognize compositor frames with stale IDs, corresponding to unloaded
> pages.
>
> BUG=672847
> CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_trusty_blink_rel;master.tryserver.chromium.linux:linux_site_isolation
>
> Review-Url: https://codereview.chromium.org/2707243005
> Cr-Commit-Position: refs/heads/master@{#454578}
> Committed: https://chromium.googlesource.com/chromium/src/+/efd1189a0b3febada2bceb4c037fff1718306a3a

TBR=enne@chromium.org,creis@chromium.org,danakj@chromium.org,kenrb@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=672847

Review-Url: https://codereview.chromium.org/2730203002
Cr-Commit-Position: refs/heads/master@{#454732}
23 files changed