Fix build.

Predeclare a function.

Unreviewed.

git-svn-id: http://skia.googlecode.com/svn/trunk@11559 2bbb7eff-a529-9590-31e7-b0007b416f81

src/images/SkScaledBitmapSampler.cpp

@@ -791,6 +791,7 @@ protected:
     }
 };
 
+void test_row_proc_choice();
 void test_row_proc_choice() {
     SkBitmap dummyBitmap;
     DummyDecoder dummyDecoder;