Roll src/third_party/skia/ dc87c9538..135c90881 (4 commits)

https://skia.googlesource.com/skia.git/+log/dc87c95382d5..135c90881287

$ git log dc87c9538..135c90881 --date=short --no-merges --format='%ad %ae %s'
2017-04-19 fmalita Remove temporary_internal_describeTopLayer
2017-04-28 caryclark add drawString helper to canvas
2017-04-28 msarett Fix bitmap copy gms
2017-04-28 msarett Only store width and height on SkPixelRef (part 1)

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
TBR=benjaminwagner@chromium.org

Change-Id: I2f1508c7c5b7248931a3e58400d146f8fe266b2c
Reviewed-on: https://chromium-review.googlesource.com/490640Reviewed-by: Skia Deps Roller <skia-deps-roller@chromium.org>
Commit-Queue: Skia Deps Roller <skia-deps-roller@chromium.org>
Cr-Commit-Position: refs/heads/master@{#468208}

DEPS

@@ -40,7 +40,7 @@ vars = {
   # 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': 'dc87c95382d5beab7fdae2e654d6de568fbe1671',
+  'skia_revision': '135c908812874e1b1ee1b9dcaf7d55544d1f8e2a',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling V8
   # and whatever else without interference from each other.