Make the canvas draw looper setup update the canvas save count

Image filter in a paint would leave save count in wrong state
for normal draws. This could be observed through the canvas
references during the draw call. An example of this is
inspecting the canvas during a draw looper.

patch from issue 993863002 at patchset 20001 (http://crrev.com/993863002#ps20001)

BUG=skia:
TBR=kkinnunen@nvidia.com

Review URL: https://codereview.chromium.org/1034033004
3 files changed