Reapply "Remove Bitmaps Raw Pixel Support."

This CL reapplies r4722. Now that we have addressed the issues
in Chrome tests that were causing asserts to be fired.

Review URL: https://codereview.appspot.com/6452050

git-svn-id: http://skia.googlecode.com/svn/trunk@4804 2bbb7eff-a529-9590-31e7-b0007b416f81
5 files changed