Force DM rebuild.

BUG=skia:

Review URL: https://codereview.chromium.org/400723002
diff --git a/dm/DM.cpp b/dm/DM.cpp
index c71450c..2a5ae54 100644
--- a/dm/DM.cpp
+++ b/dm/DM.cpp
@@ -1,5 +1,6 @@
 // Main binary for DM.
 // For a high-level overview, please see dm/README.
+//
 
 #include "CrashHandler.h"
 #include "SkCommandLineFlags.h"