Refactoring RTree integration to support SkBBoxHierarchy polymorphism in SkPicture.
This moves the rtree creation into a virtual method.
Review URL: https://codereview.appspot.com/6811057

git-svn-id: http://skia.googlecode.com/svn/trunk@6242 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/include/core/SkPicture.h b/include/core/SkPicture.h
index 72e0f5c..06c99b1 100644
--- a/include/core/SkPicture.h
+++ b/include/core/SkPicture.h
@@ -13,6 +13,7 @@
 #include "SkRefCnt.h"
 #include "SkSerializationHelpers.h"
 
+class SkBBoxHierarchy;
 class SkBitmap;
 class SkCanvas;
 class SkPicturePlayback;
@@ -154,16 +155,13 @@
     SkPictureRecord* fRecord;
     int fWidth, fHeight;
 
+    // For testing. Derived classes may instantiate an alternate
+    // SkBBoxHierarchy implementation
+    virtual SkBBoxHierarchy* createBBoxHierarchy() const;
+
 private:
     SkPicturePlayback* fPlayback;
 
-    /** Used by the R-Tree when kOptimizeForClippedPlayback_RecordingFlag is
-        set, these were empirically determined to produce reasonable performance
-        in most cases.
-    */
-    static const int kRTreeMinChildren = 6;
-    static const int kRTreeMaxChildren = 11;
-
     friend class SkFlatPicture;
     friend class SkPicturePlayback;