Resource cache now explicitly takes ref of managed resources

https://codereview.appspot.com/6489085/



git-svn-id: http://skia.googlecode.com/svn/trunk@5407 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/src/gpu/GrStencilBuffer.h b/src/gpu/GrStencilBuffer.h
index 27c0a0c..690fa32 100644
--- a/src/gpu/GrStencilBuffer.h
+++ b/src/gpu/GrStencilBuffer.h
@@ -59,8 +59,8 @@
         return fLastClipData;
     }
 
-    // places the sb in the cache and locks it. Caller transfers
-    // a ref to the the cache which will unref when purged.
+    // Places the sb in the cache and locks it. The cache takes a ref
+    // of the stencil buffer.
     void transferToCacheAndLock();
 
     static GrResourceKey ComputeKey(int width, int height, int sampleCnt);