Fix navigation to unittest files.

We have a number of instances where unit tests call UrlOf('blank.html') or something
similar. The _base_dir is src/tools/telemetry/unittest_data, so the output of relpath
is something like ../blank.html. This works because the http server just ignores the
../ and serves up http://localhost/blank.html. In the case of cros autotests, the output of
relpath ends up being something like ../../../../../../autotest/, and this doesn't work.
When running unit tests via autotest, cwd and the unittest_data directory have no common
parent. If they did, the buggy code would continue to work.

This patch introduces navigate_to_test.NavigateToTestFile, which takes a filename relative to the unittest data directory, converts it to an absolute path, sets up an http server pointing to the unittest data directory, and navigates the tab to the file as requested. tab_test_case.Navigate is a wrapper used by the majority of these unit tests.

Enable all previously failing cros unittests as well.

BUG=337582
TEST=manual

Review URL: https://codereview.chromium.org/151003003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@252253 0039d316-1c4b-4281-b951-d872f2087c98
Fixed rounding issue on scrollbar rasterization.

Changed the painting method to translate the canvas back to the
origin before performing the scale to prevent losing pixels due
to rounding. Also made the it take the layer-space rect as a 
parameter, instead of trying to reconstruct it from the 
(possibly-clamped) content-rect, and calculate the layer-space
to content-space scaling factor directly from rects.

BUG=336534

Review URL: https://codereview.chromium.org/150603004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@252254 0039d316-1c4b-4281-b951-d872f2087c98
[GCM] Fix gcm login to properly identify chrome

Use version 41 and put the chrome version in the id field.

BUG=344694

Review URL: https://codereview.chromium.org/171683002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@252255 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 252255
webkitTransitionEnd is not triggered if property change happens too fast

In certain scenario SyncSetupOverlay shows and closes very fast. In this
case according to comment for ensureTransitionEndEvent in utils.js
webkitTransitionEnd doesn't fire.

Call ensureTransitionEndEvent to make sure event fires.

R=dbeam@chromium.org
BUG=343121

Review URL: https://codereview.chromium.org/173123002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@252256 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 252256