Making SkDeferredCanvas::silentFlush trigger a skippedPendingDrawCommands callback

The bug was preventing Canvas2DLayerBridge from properly tracking changes
in memory consumption that were triggered by calls to silentFlush.

BUG=344666
TEST=DeferredCanvas unit test
R=senorblanco@google.com, senorblanco@chromium.org

Author: junov@chromium.org

Review URL: https://codereview.chromium.org/214803002

git-svn-id: http://skia.googlecode.com/svn/trunk@13965 2bbb7eff-a529-9590-31e7-b0007b416f81
2 files changed