Insert explicit casts to try appease overload resolution in the buildbots

llvm-svn: 182514

clang/lib/StaticAnalyzer/Core/BugReporter.cpp

@@ -2016,7 +2016,7 @@ static void removePunyEdges(PathPieces &path,
     if (Invalid)
       continue;
 
-    if (::abs(startCol - endCol) <= 2) {
+    if (abs((int)startCol - (int)endCol) <= 2) {
       I = path.erase(I);
       erased = true;
       continue;