Enable reference adoption run time checks for Blink+skia in Debug builds

This change enables run run time check that will help detect memory
leaks and unsafe usage in cases where Blink's RefPtr is used to
hold a reference to a skia SkRefCnt-derived object.

BUG=304265

Review URL: https://codereview.chromium.org/29763002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@230161 0039d316-1c4b-4281-b951-d872f2087c98
Roll Clang 192635:192869.

BUG=309830

Review URL: https://codereview.chromium.org/33853002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@230162 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 230161
SVN changes up to revision 230162
Remove use of WebView::setScrollbarColors API

Follow up after blink r159988.
This is in fact a noop in blink that we should remove.

r=jochen@chromium.org

Review URL: https://codereview.chromium.org/32813003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@230163 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 230163