Require that all static analyzer issues have a category.  As part of this change,
consolidate some commonly used category strings into global references (more of this can be done, I just did a few).

Fixes <rdar://problem/11191537>.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@154121 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/StaticAnalyzer/Checkers/CheckObjCInstMethSignature.cpp b/lib/StaticAnalyzer/Checkers/CheckObjCInstMethSignature.cpp
index d7321fa..6df47b1 100644
--- a/lib/StaticAnalyzer/Checkers/CheckObjCInstMethSignature.cpp
+++ b/lib/StaticAnalyzer/Checkers/CheckObjCInstMethSignature.cpp
@@ -72,6 +72,7 @@
 
     BR.EmitBasicReport(MethDerived,
                        "Incompatible instance method return type",
+                       categories::CoreFoundationObjectiveC,
                        os.str(), MethDLoc);
   }
 }