Upgrade context lost expectation to fail.

GpuCrash_GPUProcessCrashesExactlyOncePerVisitToAboutGpuCrash

This test was so flaky it was failing on the ANGLE CQ. Also affects
Intel and possibly AMD.

Tbr: kbr@chromium.org
Bug: 878258
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: I74685596e4162d1d8244ac48f60fcbd12319159d
Reviewed-on: https://chromium-review.googlesource.com/c/1286892Reviewed-by: Jamie Madill <jmadill@chromium.org>
Commit-Queue: Jamie Madill <jmadill@chromium.org>
Cr-Commit-Position: refs/heads/master@{#600489}

content/test/gpu/gpu_tests/context_lost_expectations.py

@@ -69,6 +69,6 @@ class ContextLostExpectations(GpuTestExpectations):
     self.Fail('ContextLost_WebGLContextLostFromQuantity',
               ['android', ('qualcomm', 'Adreno (TM) 420')], bug=611906)
 
-    # Temporary until Ganesh fix is made.
-    self.Flaky('GpuCrash_GPUProcessCrashesExactlyOncePerVisitToAboutGpuCrash',
-               ['win', 'nvidia'], bug=878258)
+    # Temporary until Ganesh fix is made. Too flaky to mark as flaky.
+    self.Fail('GpuCrash_GPUProcessCrashesExactlyOncePerVisitToAboutGpuCrash',
+               ['win'], bug=878258)