Currently TouchAccessibilityBrowserTest.TouchExplorationInCrossSiteIframe is using browser_test_utils::WaitForChildFrameSurfaceReady to block until a surface has submitted.

However it is not actually providing the test api with a RenderWidgetHostViewChildFrame. Currently this test api just silently exits, having performed no wait.

This means the rest of the test is racing against the actual surface activation.

A CL I have up confirms this with a CHECK: https://chromium-review.googlesource.com/c/chromium/src/+/926571

dmazzoni@ as you wrote the test could you take a look? If you have questions about frame/activation waiting I've done a lot there recently.