Fixing SkDeferredCanvas::writePixels to trigger appropriate change notifications to SkSurface

BUG=crbug.com/256269
TEST=DeferredCanvas unit test, TestDeferredCanvasWritePixelsToSurface
R=reed@google.com

Review URL: https://codereview.chromium.org/20628005

git-svn-id: http://skia.googlecode.com/svn/trunk@10513 2bbb7eff-a529-9590-31e7-b0007b416f81
2 files changed