Use ReduceClipStack in ClipMaskManager.

R=robertphillips@google.com

This will require some gpu rebaselining (complexclip_rect_aa, complexclip_aa, aaclip, simpleaaclip, complexclip_aa_layer)xy
Review URL: https://codereview.appspot.com/6884051

git-svn-id: http://skia.googlecode.com/svn/trunk@6694 2bbb7eff-a529-9590-31e7-b0007b416f81
7 files changed