Initial error handling code

include/core/SkPixelRef.h

Index: include/core/SkPixelRef.h
diff --git a/include/core/SkPixelRef.h b/include/core/SkPixelRef.h
index 64e08765bed8a3c1e1b9f3f1a652e9959b0a1865..8483c542eef5535942d568784a24c5aa09609096 100644
--- a/include/core/SkPixelRef.h
+++ b/include/core/SkPixelRef.h
@@ -45,6 +45,8 @@ class GrTexture;
     This class can be shared/accessed between multiple threads.
 */
 class SK_API SkPixelRef : public SkFlattenable {
+    typedef SkFlattenable INHERITED;
+
 public:
     SK_DECLARE_INST_COUNT(SkPixelRef)
 
@@ -207,6 +209,8 @@ public:
     virtual void globalUnref();
 #endif
 
+    SK_DEFINE_FLATTENABLE_TYPE(SkPixelRef)
+
 protected:
     /** Called when the lockCount goes from 0 to 1. The caller will have already
         acquire a mutex for thread safety, so this method need not do that.
@@ -272,8 +276,6 @@ private:
     bool    fPreLocked;
 
     void setMutex(SkBaseMutex* mutex);
-
-    typedef SkFlattenable INHERITED;
 };
 
 #endif