add drawImage to lua

git-svn-id: http://skia.googlecode.com/svn/trunk/include@9500 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/core/SkData.h b/core/SkData.h
index ab7da47..eae84b0 100644
--- a/core/SkData.h
+++ b/core/SkData.h
@@ -89,7 +89,13 @@
      *  takes ownership of that allocation, and will handling calling sk_free.
      */
     static SkData* NewFromMalloc(const void* data, size_t length);
-
+    
+    /**
+     *  Create a new dataref the file with the specified path.
+     *  If the file cannot be opened, this returns NULL.
+     */
+    static SkData* NewFromFileName(const char path[]);
+    
     /**
      *  Create a new dataref from a SkFILE.
      *  This does not take ownership of the SkFILE, nor close it.