Roll src/third_party/angle/ 14f4817c4..56c8577b4 (6 commits)

https://chromium.googlesource.com/angle/angle.git/+log/14f4817c4dad..56c8577b4dbf

$ git log 14f4817c4..56c8577b4 --date=short --no-merges --format='%ad %ae %s'
2018-04-06 cwallez TextureD3D_2D::CopyImage clear using initializeContents
2018-04-12 lucferron Vulkan: Suppress flaky test in GLSLTest on Windows
2018-04-10 brandon1.jones Autogenerate ANGLE extension entry points
2018-04-11 lucferron Vulkan: drawArrays followed by drawElements bugfix
2018-04-11 jmadill VertexArray: Use switch macro for faster iteration.
2018-04-09 lucferron Vulkan: Enable GLSLTest tests for Vulkan

Created with:
  roll-dep src/third_party/angle
BUG=chromium:827667


The AutoRoll server is located here: https://angle-chromium-roll.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=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=ynovikov@chromium.org

No-try: True
Change-Id: Ib121297476e16cae32b5198cdf8d54861a048841
Reviewed-on: https://chromium-review.googlesource.com/1011228Reviewed-by: Yuly Novikov <ynovikov@chromium.org>
Reviewed-by: angle-chromium-autoroll <angle-chromium-autoroll@skia-buildbots.google.com.iam.gserviceaccount.com>
Commit-Queue: Yuly Novikov <ynovikov@chromium.org>
Cr-Commit-Position: refs/heads/master@{#550450}

DEPS

@@ -98,7 +98,7 @@ vars = {
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling ANGLE
   # and whatever else without interference from each other.
-  'angle_revision': '14f4817c4dad9680bcb086dc651193a3f101f0aa',
+  'angle_revision': '56c8577b4dbf2239780e38090dadbeb06f4b8563',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling build tools
   # and whatever else without interference from each other.