[CI] Remove PaintInvalidator::InvalidatePaint(LocalFrameView&)

It just initializes the context, which does almost the same thing
as when the LayoutView is walked.

Change-Id: I8a4b0560bdb1da79361db8c16948f0d67aa236ce
Reviewed-on: https://chromium-review.googlesource.com/c/1394929
Reviewed-by: Philip Rogers <pdr@chromium.org>
Commit-Queue: Xianzhu Wang <wangxianzhu@chromium.org>
Cr-Commit-Position: refs/heads/master@{#619794}
3 files changed