Add RenderText DirectionalityMode enum and support; etc.
Add gfx::DirectionalityMode enum.
Add RenderText::SetDirectionalityMode and member.
Revise/consolidate RenderText::GetTextDirection.
Expand on existing unit tests; minor cleanup.
Consume GetTextDirection in layout initialization:
-Windows: RenderTextWin::ItemizeLogicalText()
-Linux: SetupPangoLayoutWithoutFont()
-Mac: Add TODO in RenderTextMac::EnsureLayout()
BUG=134746
TEST=Existing/updated unit tests, no behavioral changes!
Review URL: https://chromiumcodereview.appspot.com/10807082
git-svn-id: svn://svn.chromium.org/chrome/trunk/src@149503 0039d316-1c4b-4281-b951-d872f2087c98
16 files changed