Fix simulator build again.

Change-Id: Ifd204d64eaa4c356422e3363ec0a6e6aa61c52dc
diff --git a/libs/hwui/Matrix.cpp b/libs/hwui/Matrix.cpp
index b1eb701..68b245b 100644
--- a/libs/hwui/Matrix.cpp
+++ b/libs/hwui/Matrix.cpp
@@ -18,6 +18,7 @@
 
 #include <math.h>
 #include <stdlib.h>
+#include <string.h>
 
 #include <utils/Log.h>