Made clip mask cache use Scratch Texture system

http://codereview.appspot.com/6210044/



git-svn-id: http://skia.googlecode.com/svn/trunk@3920 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/src/gpu/GrGpu.h b/src/gpu/GrGpu.h
index de14935..aeb51f8 100644
--- a/src/gpu/GrGpu.h
+++ b/src/gpu/GrGpu.h
@@ -87,6 +87,7 @@
     void setContext(GrContext* context) {
         GrAssert(NULL == fContext); 
         fContext = context;
+        fClipMaskManager.setContext(context);
     }
     GrContext* getContext() { return fContext; }
     const GrContext* getContext() const { return fContext; }