should fix sim build, hopefully

Change-Id: I5390bd34dcca36fef43b5169386fff1b04cc842b
diff --git a/services/surfaceflinger/DisplayHardware/HWComposer.cpp b/services/surfaceflinger/DisplayHardware/HWComposer.cpp
index 518c5fe..8ca880b 100644
--- a/services/surfaceflinger/DisplayHardware/HWComposer.cpp
+++ b/services/surfaceflinger/DisplayHardware/HWComposer.cpp
@@ -15,6 +15,9 @@
  */
 
 #include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
 #include <sys/types.h>
 
 #include <utils/Errors.h>