Mark Pixel_Canvas2DTabSwitch RetryOnFailure on Nexus 5X

Renderer process is intermittently hanging; minidumps do not show why.

Bug: 1121476
Change-Id: If24d8618d7053061a51dc6acadec0c943b846a9f
Tbr: sunnyps@chromium.org
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2377653Reviewed-by: Kenneth Russell <kbr@chromium.org>
Commit-Queue: Kenneth Russell <kbr@chromium.org>
Cr-Commit-Position: refs/heads/master@{#801953}

content/test/gpu/gpu_tests/test_expectations/pixel_expectations.txt

@@ -184,6 +184,7 @@ crbug.com/1029389 [ android qualcomm-adreno-(tm)-330 ] Pixel_PrecisionRoundedCor
 crbug.com/883500 [ android-chromium no-use-gl no-use-vulkan qualcomm-adreno-(tm)-418 ] Pixel_BackgroundImage [ RetryOnFailure ]
 crbug.com/1068620 [ android android-chromium no-use-gl no-use-vulkan qualcomm-adreno-(tm)-418 ] Pixel_OffscreenCanvasWebGLPaintAfterResize [ RetryOnFailure ]
 crbug.com/1065514 [ android android-chromium qualcomm-adreno-(tm)-418 ] Pixel_WebGLReadPixelsTabSwitch [ RetryOnFailure ]
+crbug.com/1121476 [ android android-chromium qualcomm-adreno-(tm)-418 ] Pixel_Canvas2DTabSwitch [ RetryOnFailure ]
 
 # We do not have software H.264 decoding on Android, so it can't survive a
 # context loss which results in hardware decoder loss.