Disable ContextLost_WebGLUnblockedAfterUserInitiatedReload

gpu_tests.context_lost_integration_test.ContextLostIntegrationTest.ContextLost_WebGLUnblockedAfterUserInitiatedReload in context_lost_tests
is flaky on Win10 Debug

TBR=kbr@chromium.org

Bug: 895765, 879423
Change-Id: Ic36400494df68f257329e040be2c72f1ad2ec3a6
Reviewed-on: https://chromium-review.googlesource.com/c/1283049
Commit-Queue: Christos Froussios <cfroussios@chromium.org>
Reviewed-by: Christos Froussios <cfroussios@chromium.org>
Cr-Commit-Position: refs/heads/master@{#599973}

content/test/gpu/gpu_tests/context_lost_expectations.py

@@ -27,6 +27,10 @@ class ContextLostExpectations(GpuTestExpectations):
     self.Skip('ContextLost_WebGLContextLostFromSelectElement',
               ['win8', 'nvidia'], bug=524808)
 
+    # Flaky on Win10
+    self.Flaky('ContextLost_WebGLUnblockedAfterUserInitiatedReload',
+              ['win10', 'debug'], bug=895765)
+
     # Flakily timing out on Win x64 Debug bot.
     # Unfortunately we can't identify this separately from the 32-bit bots.
     # Also unfortunately, the flaky retry mechanism doesn't work well in