For example on flutter/engine#34289, the bot asked for approval for diffs on a Dart SDK -> Engine roll, but that should not be happening.

Edit: In investigating these roll blockages, we determined that the real problem was that the ExternalTextureTests that were recently enabled by flutter/engine#34118 are flaky. One issue is that the wrong value is being used for the image size. This should be addressed by flutter/engine#34431. However, the images that the test produces are still toggling back and forth between 2 or more variants, which causes skia diffs on PRs in a flaky way. The tests were disabled by flutter/engine#34433, but should be re-enabled as a P0 since they are one of the only places we have test coverage of platform views.