The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/f262dcd39cd2976372d52af9fbfaab791284dbbf

commit f262dcd39cd2976372d52af9fbfaab791284dbbf
Author: David Bokan <bokan@chromium.org>
Date: Fri Mar 02 21:21:26 2018

[root-layer-scrolls] Fix scrollable-area tests

These tests were failing on Android when RootLayerScrolls is turned on.
The reason being that the frame now scrolls with a
PaintLayerScrollableArea. This PLSA is now unexpectedly added the the
Frame's ScrollableAreaSet just like any other scroller so the count is
changed. I've confirmed in all references to the ScrollableAreaSet that
including the main scroller should be correct so this is just a matter
of fixing the tests.

The reason these tests fail only on Android is because, on desktop,
the frame doesn't have any overflow so the ScrollableArea isn't added
to the set. On Android, the content loads using the legacy 980px width
but the test is performed before the main frame is resized to match the
content width so we're still in a state of overflow. The fix here is to
add a viewport meta tag so the content width matches the device
viewport, just like on desktop.

I also fixed all other tests in this family in the same way which
removes one additional entry from TestExpectations. The other tests
aren't run on Android but I've confirmed this makes them pass if they're
manually run.

Bug:  817426 
Change-Id: I5a72a82402514bb28f6d915283553c7bdf777330
Reviewed-on: https://chromium-review.googlesource.com/946871
Reviewed-by: Philip Rogers <pdr@chromium.org>
Commit-Queue: David Bokan <bokan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#540628}
[modify] https://crrev.com/f262dcd39cd2976372d52af9fbfaab791284dbbf/third_party/WebKit/LayoutTests/TestExpectations
[modify] https://crrev.com/f262dcd39cd2976372d52af9fbfaab791284dbbf/third_party/WebKit/LayoutTests/fast/scrolling/scrollable-area-dynamic-overflow.html
[modify] https://crrev.com/f262dcd39cd2976372d52af9fbfaab791284dbbf/third_party/WebKit/LayoutTests/fast/scrolling/scrollable-area-frame-overflow-hidden.html
[modify] https://crrev.com/f262dcd39cd2976372d52af9fbfaab791284dbbf/third_party/WebKit/LayoutTests/fast/scrolling/scrollable-area-frame-overried-inherited-visibility-hidden.html
[modify] https://crrev.com/f262dcd39cd2976372d52af9fbfaab791284dbbf/third_party/WebKit/LayoutTests/fast/scrolling/scrollable-area-frame-scrolling-no-overried-inherited-visibility-hidden.html
[modify] https://crrev.com/f262dcd39cd2976372d52af9fbfaab791284dbbf/third_party/WebKit/LayoutTests/fast/scrolling/scrollable-area-frame-scrolling-no-visibility-hidden-child.html
[modify] https://crrev.com/f262dcd39cd2976372d52af9fbfaab791284dbbf/third_party/WebKit/LayoutTests/fast/scrolling/scrollable-area-frame-scrolling-no.html
[modify] https://crrev.com/f262dcd39cd2976372d52af9fbfaab791284dbbf/third_party/WebKit/LayoutTests/fast/scrolling/scrollable-area-frame-scrolling-yes.html
[modify] https://crrev.com/f262dcd39cd2976372d52af9fbfaab791284dbbf/third_party/WebKit/LayoutTests/fast/scrolling/scrollable-area-frame-visibility-hidden-child.html
[modify] https://crrev.com/f262dcd39cd2976372d52af9fbfaab791284dbbf/third_party/WebKit/LayoutTests/fast/scrolling/scrollable-area-frame-zero-size-and-border.html
[modify] https://crrev.com/f262dcd39cd2976372d52af9fbfaab791284dbbf/third_party/WebKit/LayoutTests/fast/scrolling/scrollable-area-frame.html
[modify] https://crrev.com/f262dcd39cd2976372d52af9fbfaab791284dbbf/third_party/WebKit/LayoutTests/fast/scrolling/scrollable-area-overflow-auto-display-none-in-parent.html
[modify] https://crrev.com/f262dcd39cd2976372d52af9fbfaab791284dbbf/third_party/WebKit/LayoutTests/fast/scrolling/scrollable-area-overflow-auto-display-none.html
[modify] https://crrev.com/f262dcd39cd2976372d52af9fbfaab791284dbbf/third_party/WebKit/LayoutTests/fast/scrolling/scrollable-area-overflow-auto-visibility-hidden-in-parent.html
[modify] https://crrev.com/f262dcd39cd2976372d52af9fbfaab791284dbbf/third_party/WebKit/LayoutTests/fast/scrolling/scrollable-area-overflow-auto-visibility-hidden.html
[modify] https://crrev.com/f262dcd39cd2976372d52af9fbfaab791284dbbf/third_party/WebKit/LayoutTests/fast/scrolling/scrollable-area-overflow-auto-visibility-override.html
[modify] https://crrev.com/f262dcd39cd2976372d52af9fbfaab791284dbbf/third_party/WebKit/LayoutTests/fast/scrolling/scrollable-area-overflow-auto-visibility-visible.html
[modify] https://crrev.com/f262dcd39cd2976372d52af9fbfaab791284dbbf/third_party/WebKit/LayoutTests/fast/scrolling/scrollable-area-overflow-auto.html
[modify] https://crrev.com/f262dcd39cd2976372d52af9fbfaab791284dbbf/third_party/WebKit/LayoutTests/fast/scrolling/scrollable-area-overflow-not-set.html
[modify] https://crrev.com/f262dcd39cd2976372d52af9fbfaab791284dbbf/third_party/WebKit/LayoutTests/fast/scrolling/scrollable-area-overflow-visible.html

This was an issue with tests - no merge necessary.