Add blurb about leak sanitizer.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/branches/release_34@197417 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/docs/ReleaseNotes.rst b/docs/ReleaseNotes.rst
index 9a17bef..076c5e5 100644
--- a/docs/ReleaseNotes.rst
+++ b/docs/ReleaseNotes.rst
@@ -1,6 +1,6 @@
-=====================================
-Clang 3.4 (In-Progress) Release Notes
-=====================================
+=======================
+Clang 3.4 Release Notes
+=======================
 
 .. contents::
    :local:
@@ -94,6 +94,9 @@
   + Various performance improvements when searching for typo correction
     candidates.
 
+- `LeakSanitizer <LeakSanitizer.rst>`_ is an experimental memory leak detector
+  which can be combined with AddressSanitizer.
+
 New Compiler Flags
 ------------------