Roll src/third_party/skia/ 5cb5c74ef..34a388edb (5 commits; 2 trivial rolls)

https://skia.googlesource.com/skia.git/+log/5cb5c74efdac..34a388edbd27

$ git log 5cb5c74ef..34a388edb --date=short --no-merges --format='%ad %ae %s'
2018-04-27 csmartdalton ccpr: Remove canMakeClipProcessor
2018-04-27 liyuqian Reland "Reland "Reland "Exercise the threaded backend in test bots"""
2018-04-27 brianosman Add ASYNC trace macros

Created with:
  roll-dep src/third_party/skia


The AutoRoll server is located here: https://autoroll.skia.org

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

If the roll is causing failures, please contact the current sheriff, who should
be CC'd on the roll, and stop the roller if necessary.


CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_trusty_blink_rel;luci.chromium.try:android_optional_gpu_tests_rel;luci.chromium.try:linux_optional_gpu_tests_rel;luci.chromium.try:mac_optional_gpu_tests_rel;luci.chromium.try:win_optional_gpu_tests_rel
TBR=stani@chromium.org

Change-Id: Id312399ace42628fc464aecb6415d5f2dad79707
Reviewed-on: https://chromium-review.googlesource.com/1033717Reviewed-by: skia-chromium-autoroll <skia-chromium-autoroll@skia-buildbots.google.com.iam.gserviceaccount.com>
Commit-Queue: skia-chromium-autoroll <skia-chromium-autoroll@skia-buildbots.google.com.iam.gserviceaccount.com>
Cr-Commit-Position: refs/heads/master@{#554564}

DEPS

@@ -90,7 +90,7 @@ 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': '5cb5c74efdac46a1f9af37ff9707bc9d2c900083',
+  'skia_revision': '34a388edbd277cf23d55627695b4bb6c46230d22',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling V8
   # and whatever else without interference from each other.