Use scratch keys for stencil buffers.

src/gpu/GrGpu.cpp

Index: src/gpu/GrGpu.cpp
diff --git a/src/gpu/GrGpu.cpp b/src/gpu/GrGpu.cpp
index 2bda594b9a37a12f8ccbbcb1a66999ec8aa24441..6b742c4cc3db069150cb719b262091a67cb69492 100644
--- a/src/gpu/GrGpu.cpp
+++ b/src/gpu/GrGpu.cpp
@@ -13,14 +13,12 @@
 #include "GrContext.h"
 #include "GrDrawTargetCaps.h"
 #include "GrIndexBuffer.h"
+#include "GrResourceCache2.h"
 #include "GrStencilBuffer.h"
 #include "GrVertexBuffer.h"
 
 ////////////////////////////////////////////////////////////////////////////////
 
-#define DEBUG_INVAL_BUFFER    0xdeadcafe
-#define DEBUG_INVAL_START_IDX -1
-
 GrGpu::GrGpu(GrContext* context)
     : fResetTimestamp(kExpiredTimestamp+1)
     , fResetBits(kAll_GrBackendState)
@@ -78,8 +76,9 @@ GrTexture* GrGpu::createTexture(const GrSurfaceDesc& desc,
 
 bool GrGpu::attachStencilBufferToRenderTarget(GrRenderTarget* rt) {
     SkASSERT(NULL == rt->getStencilBuffer());
-    SkAutoTUnref<GrStencilBuffer> sb(
-        this->getContext()->findAndRefStencilBuffer(rt->width(), rt->height(), rt->numSamples()));
+    GrResourceKey sbKey = GrStencilBuffer::ComputeKey(rt->width(), rt->height(), rt->numSamples());
+    SkAutoTUnref<GrStencilBuffer> sb(static_cast<GrStencilBuffer*>(
+        this->getContext()->getResourceCache2()->findAndRefScratchResource(sbKey)));
     if (sb) {
         rt->setStencilBuffer(sb);
         bool attached = this->attachStencilBufferToRenderTarget(sb, rt);