Roll src/third_party/skia/ ffaa47e0f..7a8c84c6c (8 commits; 1 trivial rolls)

https://skia.googlesource.com/skia.git/+log/ffaa47e0fe5f..7a8c84c6c925

$ git log ffaa47e0f..7a8c84c6c --date=short --no-merges --format='%ad %ae %s'
2017-06-12 ericrk Reland DeferredTextureImageData low-bit-depth/dithering support
2017-06-12 msarett Revert "Revert "Disable F16-nullptr sources""
2017-06-12 mtklein fix f16 encoding
2017-06-12 csmartdalton Convert SkClassifyCubic to double precision
2017-06-12 senorblanco GrTessellator: fix two NaN issues.
2017-06-12 benjaminwagner [infra] Isolate tasks don't need compile task.
2017-06-12 reed enable rasterpipeline for android

Created with:
  roll-dep src/third_party/skia


Documentation for the AutoRoller is here:
https://skia.googlesource.com/buildbot/+/master/autoroll/README.md

If the roll is causing failures, see:
http://www.chromium.org/developers/tree-sheriffs/sheriff-details-chromium#TOC-Failures-due-to-DEPS-rolls


CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_trusty_blink_rel;master.tryserver.chromium.linux:linux_optional_gpu_tests_rel;master.tryserver.chromium.mac:mac_optional_gpu_tests_rel;master.tryserver.chromium.win:win_optional_gpu_tests_rel;master.tryserver.chromium.android:android_optional_gpu_tests_rel
[email protected]

Change-Id: I343d7c3cbe318abc3deb57ee0df53931ab90397d
Reviewed-on: https://chromium-review.googlesource.com/531800
Reviewed-by: Skia Deps Roller <[email protected]>
Commit-Queue: Skia Deps Roller <[email protected]>
Cr-Commit-Position: refs/heads/master@{#478746}
diff --git a/DEPS b/DEPS
index 02072c2..b9ff372 100644
--- a/DEPS
+++ b/DEPS
@@ -40,7 +40,7 @@
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling Skia
   # and whatever else without interference from each other.
-  'skia_revision': 'ffaa47e0fe5fca8aa19fd08414480bd73b6e4daa',
+  'skia_revision': '7a8c84c6c92565842aeea27d4971fbd78d523f7a',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling V8
   # and whatever else without interference from each other.