Suppress ContextLost_WebGLBlockedAfterJSNavigation flake on Android.

GPU process bringup is flaky while the tests are crashing the GPU
process. Similar suppressions may ultimately be needed for other GPU
process crash tests on Android.

Bug: 882103
No-Try: True
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
Change-Id: I4326e81a9f8e64066b1ac271fc87e9afa97a8681
Tbr: enne@chromium.org
Reviewed-on: https://chromium-review.googlesource.com/1217403Reviewed-by: Kenneth Russell <kbr@chromium.org>
Commit-Queue: Kenneth Russell <kbr@chromium.org>
Cr-Commit-Position: refs/heads/master@{#590042}

content/test/gpu/gpu_tests/context_lost_expectations.py

@@ -55,8 +55,14 @@ class ContextLostExpectations(GpuTestExpectations):
               ['android'], bug=609629)
 
     # Flaking on Nexus 5X
+    self.Flaky('ContextLost_WebGLBlockedAfterJSNavigation',
+               ['android'], bug=882103)
     self.Flaky('ContextLost_WebGLUnblockedAfterUserInitiatedReload',
               ['android'], bug=879423)
+    self.Fail('ContextLost_WorkerRAFAfterGPUCrash',
+              ['android'], bug=880078)
+    self.Fail('ContextLost_WorkerRAFAfterGPUCrash_OOPD',
+              ['android'], bug=880078)
 
     # Nexus 6
     # The Nexus 6 times out on these tests while waiting for the JS to complete
@@ -64,9 +70,3 @@ class ContextLostExpectations(GpuTestExpectations):
               ['android', ('qualcomm', 'Adreno (TM) 420')], bug=611906)
     self.Fail('ContextLost_WebGLContextLostFromQuantity',
               ['android', ('qualcomm', 'Adreno (TM) 420')], bug=611906)
-
-    # Android
-    self.Fail('ContextLost_WorkerRAFAfterGPUCrash',
-              ['android'], bug=880078)
-    self.Fail('ContextLost_WorkerRAFAfterGPUCrash_OOPD',
-              ['android'], bug=880078)