Remove SkQuadTree.

src/core/SkBBHFactory.cpp

Index: src/core/SkBBHFactory.cpp
diff --git a/src/core/SkBBHFactory.cpp b/src/core/SkBBHFactory.cpp
index 21a95fe0582a38fecbe5b96d03b1dfd47ab6d2cc..c895ff60fbc83be722c2ebce76b70c0260d9a284 100644
--- a/src/core/SkBBHFactory.cpp
+++ b/src/core/SkBBHFactory.cpp
@@ -6,15 +6,10 @@
  */
 
 #include "SkBBHFactory.h"
-#include "SkQuadTree.h"
 #include "SkRTree.h"
 #include "SkTileGrid.h"
 
 
-SkBBoxHierarchy* SkQuadTreeFactory::operator()(int width, int height) const {
-    return SkNEW_ARGS(SkQuadTree, (SkIRect::MakeWH(width, height)));
-}
-
 SkBBoxHierarchy* SkRTreeFactory::operator()(int width, int height) const {
     // These values were empirically determined to produce reasonable
     // performance in most cases.