Added platform specific includes


git-svn-id: http://skia.googlecode.com/svn/trunk@1696 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/include/utils/mac/SkCGUtils.h b/include/utils/mac/SkCGUtils.h
index 06bb85c..aba6467 100644
--- a/include/utils/mac/SkCGUtils.h
+++ b/include/utils/mac/SkCGUtils.h
@@ -7,6 +7,10 @@
 #include <ApplicationServices/ApplicationServices.h>
 #endif
 
+#ifdef SK_BUILD_FOR_IOS
+#include <CoreGraphics/CoreGraphics.h>
+#endif
+
 class SkBitmap;
 
 /**