Fix GrTextureAccess::operator ==

compare the textures, correctly intepret memcmp result, don't compare last byte of swizzle array which must be 0.

BUG=895
Review URL: https://codereview.appspot.com/6542048

git-svn-id: http://skia.googlecode.com/svn/trunk@5605 2bbb7eff-a529-9590-31e7-b0007b416f81
1 file changed