Update clang to r339409b.

Change-Id: Ied8a188bb072c40035320acedc86164b66d920af
diff --git a/linux-x64/clang/include/llvm/Support/Timer.h b/linux-x64/clang/include/llvm/Support/Timer.h
index bfffbc3..a11c3ce 100644
--- a/linux-x64/clang/include/llvm/Support/Timer.h
+++ b/linux-x64/clang/include/llvm/Support/Timer.h
@@ -206,15 +206,23 @@
     Description.assign(NewDescription.begin(), NewDescription.end());
   }
 
-  /// Print any started timers in this group and zero them.
+  /// Print any started timers in this group.
   void print(raw_ostream &OS);
 
-  /// This static method prints all timers and clears them all out.
+  /// Clear all timers in this group.
+  void clear();
+
+  /// This static method prints all timers.
   static void printAll(raw_ostream &OS);
 
+  /// Clear out all timers. This is mostly used to disable automatic
+  /// printing on shutdown, when timers have already been printed explicitly
+  /// using \c printAll or \c printJSONValues.
+  static void clearAll();
+
   const char *printJSONValues(raw_ostream &OS, const char *delim);
 
-  /// Prints all timers as JSON key/value pairs, and clears them all out.
+  /// Prints all timers as JSON key/value pairs.
   static const char *printAllJSONValues(raw_ostream &OS, const char *delim);
 
   /// Ensure global timer group lists are initialized. This function is mostly