Simplified stencil buffer caching

https://codereview.appspot.com/6503073/



git-svn-id: http://skia.googlecode.com/svn/trunk@5400 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/src/gpu/gl/GrGLRenderTarget.cpp b/src/gpu/gl/GrGLRenderTarget.cpp
index 16d7f1b..3e72757 100644
--- a/src/gpu/gl/GrGLRenderTarget.cpp
+++ b/src/gpu/gl/GrGLRenderTarget.cpp
@@ -92,7 +92,7 @@
     fMSColorRenderbufferID  = 0;
     GrSafeUnref(fTexIDObj);
     fTexIDObj = NULL;
-    this->setStencilBuffer(NULL);
+    INHERITED::onRelease();
 }
 
 void GrGLRenderTarget::onAbandon() {
@@ -103,6 +103,6 @@
         fTexIDObj->abandon();
         fTexIDObj = NULL;
     }
-    this->setStencilBuffer(NULL);
+    INHERITED::onAbandon();
 }