tree 9a7326ace2054faecd8ca907e90188b412be7b54
parent 9f13174da5295e88d447f29740318003b9cec9c3
author reed@google.com <reed@google.com@2bbb7eff-a529-9590-31e7-b0007b416f81> 1355434796 +0000
committer reed@google.com <reed@google.com@2bbb7eff-a529-9590-31e7-b0007b416f81> 1355434796 +0000

Goal: ensure we always balance lock/unlock pixels calls.

A big caller of lockPixels is setContext in the bitmapshader.

This change replaces beginSession/endSession with adding endContext(), and
adds debugging code to ensure that
1. setContext calls are never nested
2. endContext is always called after each setContext call.
Review URL: https://codereview.appspot.com/6937046

git-svn-id: http://skia.googlecode.com/svn/trunk@6798 2bbb7eff-a529-9590-31e7-b0007b416f81