Really fix valgrind issue

TBR=
BUG=skia:

Review URL: https://codereview.chromium.org/795123002
rebase hairlines

TBR=
BUG=skia:

Review URL: https://codereview.chromium.org/795133002
Defer saves() until they're needed

patch from issue 759443006 at patchset 40001 (http://crrev.com/759443006#ps40001)

BUG=skia:

Review URL: https://codereview.chromium.org/767333002
update test after I added a clip call, making the count odd

BUG=skia:
TBR=
NOTREECHECKS=True
NOTRY=True

Review URL: https://codereview.chromium.org/797633002
rebase cpu hairlines

NOTRY=True
NOTREECHECKS=True
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BUG=skia:

Review URL: https://codereview.chromium.org/793393002
Apply the layer's image filter to the hoisted image

Exposing SkSurface_Gpu makes me sad and I would welcome alternatives.

This change is desireable since it greatly decreases the render target swaps.

Review URL: https://codereview.chromium.org/792923002
Poppler rebaseline for clipped-bitmap-shaders-clamp

Follow-up for https://codereview.chromium.org/787043006.

TBR=scroggo@google.com

Review URL: https://codereview.chromium.org/798533003