Issue 755318  has been merged into this issue.

Landed a replacement for ScrollWaiter in: https://chromium-review.googlesource.com/c/chromium/src/+/947036

Landed the re-enabling in https://chromium-review.googlesource.com/c/chromium/src/+/977893/1

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/082707af4c53d7a511c63e0563ea304f080222f9

commit 082707af4c53d7a511c63e0563ea304f080222f9
Author: jonross <jonross@chromium.org>
Date: Fri Mar 23 14:14:30 2018

Replace WebViewBrowserTest::ScrollWaiter

WebViewBrowserTest::ScrollWaiter does not work in Viz. This change replaces it
with RenderFrameSubmissionObserver which provides the same functionality for
both normal and viz display compositors.

Also swaps all GetLastScrollOffset calls over to RenderFrameSubmissionObserver.
As they also don't work in Viz.

TEST=WebViewBrowserTest*

Bug:  796336 
Change-Id: I7cebf3d3ac2d4ecc0c6f3cf208e5ba691eadad6e
Reviewed-on: https://chromium-review.googlesource.com/947036
Commit-Queue: Jonathan Ross <jonross@chromium.org>
Reviewed-by: Antoine Labour <piman@chromium.org>
Reviewed-by: Fady Samuel <fsamuel@chromium.org>
Cr-Commit-Position: refs/heads/master@{#545430}
[modify] https://crrev.com/082707af4c53d7a511c63e0563ea304f080222f9/chrome/browser/apps/guest_view/web_view_browsertest.cc
[modify] https://crrev.com/082707af4c53d7a511c63e0563ea304f080222f9/content/public/test/browser_test_utils.cc
[modify] https://crrev.com/082707af4c53d7a511c63e0563ea304f080222f9/content/public/test/browser_test_utils.h
[modify] https://crrev.com/082707af4c53d7a511c63e0563ea304f080222f9/content/renderer/render_frame_metadata_observer_impl.cc
[modify] https://crrev.com/082707af4c53d7a511c63e0563ea304f080222f9/content/renderer/render_frame_metadata_observer_impl.h
[modify] https://crrev.com/082707af4c53d7a511c63e0563ea304f080222f9/testing/buildbot/filters/mash.browser_tests.filter

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/fde97876e50ea6b0501da2e06b0fa13461f8eaa8

commit fde97876e50ea6b0501da2e06b0fa13461f8eaa8
Author: jonross <jonross@chromium.org>
Date: Fri Mar 23 14:52:02 2018

Re-enable WebViewGuestScrollTouchTest.TestGuestGestureScrollsBubble on Viz

I landed a replacement for ScrollWaiter which also works in Viz, but forgot to
re-enable the tests on viz configs. Doing that now.

TBR=kylechar@chromium.org
TEST=WebViewGuestScrollTouchTest.TestGuestGestureScrollsBubble

Bug:  796336 
Change-Id: Ifdee622aa2f8267623698c5f71b10a0b1da5bee8
Reviewed-on: https://chromium-review.googlesource.com/977893
Reviewed-by: Jonathan Ross <jonross@chromium.org>
Cr-Commit-Position: refs/heads/master@{#545444}
[modify] https://crrev.com/fde97876e50ea6b0501da2e06b0fa13461f8eaa8/testing/buildbot/filters/viz.browser_tests.filter