Rework the retain-release.m test to use FileCheck and the "text" output

of the analyzer, as the RetainReleaseChecker has many fine-grain
path diagnostic events that were not being checked.  This uncovered
an inconsistency between the path diagnostics between Objective-C
and Objective-C++ code in ConditionBRVisitor that was fixed in a recent
patch.

llvm-svn: 163373