First attempt to flip flag at
https://codereview.chromium.org/2941113002/

The failures mostly seem related to tab capture and screenshot. Leaving this as a single bug because I'm pretty sure the root cause is the same for all of them

telemetry_unittests:
telemetry.internal.backends.chrome_inspector.inspector_page_unittest.InspectorPageTest.testCaptureScreenshot

browser_tests:
TabCaptureApiPixelTest.EndToEndWithoutRemoting (and others)

content_browsertests:
GLAndSoftwareCompositing/CompositingRenderWidgetHostViewBrowserTestTabCapture.CopyFromSurface_Origin_Scaled/0 (among others)

pixel_test:
gpu_tests.pixel_integration_test.PixelIntegrationTest.Pixel_WebGLGreenTriangle_NoAA_NoAlpha (and everything else)

screenshot_sync_tests:
gpu_tests.screenshot_sync_integration_test.ScreenshotSyncIntegrationTest.ScreenshotSync_*

tab_capture_end2end_tests:
TabCaptureApiPixelTest.EndToEndWithoutRemoting