ShellTest.ResubmitFrame is flakey for linux #68540
Description
Examples:
- https://ci.chromium.org/p/flutter/builders/prod/Linux%20Host%20Engine/7319
- https://ci.chromium.org/p/flutter/builders/prod/Linux%20Host%20Engine/7258
Text:
[ RUN ] ShellTest.ResubmitFrame
../../flutter/shell/common/shell_unittests.cc:1076: Failure
Expected equality of these values:
1
external_view_embedder->GetSubmittedFrameCount()
Which is: 2
flutter/engine#21831 was reverted for this flake but now it seems to have manifested itself without that PR.