Code changed in jenkins
User: Andrew Bayer
[FIXED JENKINS-48020] Show stage in failed tests, fix warnings
First, this changes `CaseResult#getFullDisplayName()` to include
stage/branch names like `CaseResult#getDisplayName()`, so that the
full information will show up in lists of failed tests, for example.
Second, stop using `CaseResult#getDisplayName()` for indexing
`CaseResult`s in `SuiteResult`. That method will spam warnings if
called too early in the run now due to `CaseResult#getRun()` being
called before the `SuiteResult`'s parent is set.
Third, fix `JUnitResultsStepTest#testTrends` to actually test what
it's supposed to, to fail if it doesn't find the expected display
names, to test full display names as well, and to use the same
filename for the test results each time due to one of the stages' test
file not containing an explicit suite name, leading to its suite's
name being set to the filename, breaking `SuiteResult#getPreviousResult()`.