Update clang to r339409.

Change-Id: I800772d2d838223be1f6b40d490c4591b937fca2
diff --git a/linux-x64/clang/include/llvm/ADT/SmallPtrSet.h b/linux-x64/clang/include/llvm/ADT/SmallPtrSet.h
index 78ea613..db08e40 100644
--- a/linux-x64/clang/include/llvm/ADT/SmallPtrSet.h
+++ b/linux-x64/clang/include/llvm/ADT/SmallPtrSet.h
@@ -335,7 +335,7 @@
   enum { Val = RoundUpToPowerOfTwoH<N, (N&(N-1)) == 0>::Val };
 };
 
-/// \brief A templated base class for \c SmallPtrSet which provides the
+/// A templated base class for \c SmallPtrSet which provides the
 /// typesafe interface that is common across all small sizes.
 ///
 /// This is particularly useful for passing around between interface boundaries