Rerun the back buffer test if front buffer test fails.
Since the FrontBuffer option was taken out, the testing framework will first test the backbuffer, and if that fails, then test the front buffer. However, if a test fails, the images uploaded to CDash show the wrong data. For instance: https://open.cdash.org/testDetails.php?test=373277492&build=4009262 shows the valid image as completely black, while the actual failure: https://open.cdash.org/testDetails.php?test=374725352&build=4016849 shows that the number of labels displayed has changed.
Showing with 14 additions and 3 deletions