Use different icons for errors and failures #744
Description
JUnit distinguishes between failures (where the test reports an issue, usually via an assertion) and errors (where the test could not be run successfully, usually due to a non-assertion exception).
While I am fine combining their numbers in the main pass/fail/skip breakdown tally, it would be useful to be able to spot the difference in the test list, and currently both cases use the same icon. (My suggestion would be to keep that for failures and use the orange 'unstable' icon for errors, but in the end the specific icon matters little.)