Pass SourceRanges by reference to the various Diag methods.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@55284 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Parse/Parser.cpp b/lib/Parse/Parser.cpp
index c6b0a80..7598ff7 100644
--- a/lib/Parse/Parser.cpp
+++ b/lib/Parse/Parser.cpp
@@ -39,7 +39,7 @@
 }
 
 bool Parser::Diag(SourceLocation Loc, unsigned DiagID, const std::string &Msg,
-                  SourceRange Range) {
+                  const SourceRange& Range) {
   Diags.Report(PP.getFullLoc(Loc), DiagID, &Msg, 1, &Range,1);
   return true;
 }