Refactor: Simplify boolean conditional return statements in lib/Lex

Summary: Use clang-tidy to simplify boolean conditional return statements

Reviewers: dblaikie

Subscribers: dblaikie, cfe-commits

Patch by Richard Thomson!

Differential Revision: http://reviews.llvm.org/D10017

llvm-svn: 256499
diff --git a/clang/lib/Lex/PPMacroExpansion.cpp b/clang/lib/Lex/PPMacroExpansion.cpp
index 2497e5e..18348df 100644
--- a/clang/lib/Lex/PPMacroExpansion.cpp
+++ b/clang/lib/Lex/PPMacroExpansion.cpp
@@ -597,9 +597,7 @@
       Brackets.pop_back();
     }
   }
-  if (!Brackets.empty())
-    return false;
-  return true;
+  return Brackets.empty();
 }
 
 /// GenerateNewArgTokens - Returns true if OldTokens can be converted to a new