Use mocked scrollbar in webkit unit tests

Use mocked scrollbar in webkit unit tests

A webkit unit test will crash in chromium code if a scrollbar using
native theme is painted, because the required resources are not loaded
in webkit unit tests.

Synchronized painting would cause some unit tests previously didn't
crash to crash.

Use mocked scrollbar for these unit tests.

BUG=536999
Committed: https://crrev.com/2cfdf53e287eac60d29e58002fbe35d81977184a
Cr-Commit-Position: refs/heads/master@{#356997}

[Xianzhu, 2015-10-29 22:56:22]

wangxianzhu@chromium.org changed reviewers:
+ chrishtr@chromium.org, schenney@chromium.org

[Xianzhu, 2015-10-29 22:56:23]

schenney@ I was told you are planning to remove mocked scrollbars. This CL added
usages of mocked scrollbars, but actually using mocked overlay scrollbars whose
theme is almost the same as the normal non-mac scrollbars. Please let me know
any problem of this CL.

[chrishtr, 2015-10-29 23:08:43]

https://codereview.chromium.org/1413513009/diff/1/third_party/WebKit/Source/w...
File third_party/WebKit/Source/web/tests/WebFrameTest.cpp (left):

https://codereview.chromium.org/1413513009/diff/1/third_party/WebKit/Source/w...
third_party/WebKit/Source/web/tests/WebFrameTest.cpp:943:
UseMockScrollbarSettings mockScrollbarSettings;
Why remove all these?

[Xianzhu, 2015-10-29 23:40:28]

https://codereview.chromium.org/1413513009/diff/1/third_party/WebKit/Source/w...
File third_party/WebKit/Source/web/tests/WebFrameTest.cpp (left):

https://codereview.chromium.org/1413513009/diff/1/third_party/WebKit/Source/w...
third_party/WebKit/Source/web/tests/WebFrameTest.cpp:943:
UseMockScrollbarSettings mockScrollbarSettings;
On 2015/10/29 23:08:43, chrishtr wrote:
> Why remove all these?

I put UseMockScrollbarSettings m_mockScrollbarSettings in WebFrameTest, so we
don't need to put this in every test case.

[chrishtr, 2015-10-30 00:16:05]

The CQ bit was checked by chrishtr@chromium.org

[chrishtr, 2015-10-30 00:16:06]

lgtm

[commit-bot: I haz the power, 2015-10-30 00:17:11]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1413513009/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1413513009/1

[commit-bot: I haz the power, 2015-10-30 00:22:33]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-10-30 00:23:24]

Patchset 1 (id:??) landed as
https://crrev.com/2cfdf53e287eac60d29e58002fbe35d81977184a
Cr-Commit-Position: refs/heads/master@{#356997}