The bottom window (remote - stdout) is the result of rerunning any failing tests.

Note that Phabricator does indeed *not* run a full validate on patches or commits (i.e. it does not run `./validate --slow`), because it would take too long (Harbormaster is already having problems with the current load it gets), and would only sporadically catch a bug that `./validate (--normal)` would not have caught. When you add a new test yourself, and you want to be sure it also passes `validate --slow`, please run that test locally using `make TEST=<testname> slow` in the testsuite directory. 

The different speed settings of the testsuite are explained on  https://ghc.haskell.org/trac/ghc/wiki/Building/RunningTests/Running#Speedsettings and in `Note [validate and testsuite speed]` in the toplevel Makefile.