$DEPS is now funny, it is an unexpanded string using the shell
variable $GEN_DIR. Upstream buck suggests using $(eval echo $DEPS)
to access the string value as $DEPS will not expand to the complete
file paths.
Instead of using eval modify our only use of $DEPS inside of the
GWT compiler helper to replace $GEN_DIR at the start of a string
with the value from the environment.
The JUnit support in Buck was updated recently and PrologTestCase
is being identified as a test to run. Rename its execution method
to prevent it from being identified as a test and push real call
down into the concrete base class.
Change-Id: Ic7e119cd26e72ee95e155e8507785c77b7692acf
627a250c72