Fix key computation for GrPaths

src/gpu/GrPath.h

 /*
  * Copyright 2012 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef GrPath_DEFINED
 #define GrPath_DEFINED
 
 #include "GrGpuResource.h"
 #include "GrPathRendering.h"
 #include "GrStyle.h"
 #include "SkPath.h"
 #include "SkRect.h"
 
+class GrShape;
+
 class GrPath : public GrGpuResource {
 public:
     /**
      * Initialize to a path with a fixed stroke. Stroke must not be hairline.
      */
     GrPath(GrGpu* gpu, const SkPath& skPath, const GrStyle& style)
         : INHERITED(gpu)
         , fBounds(SkRect::MakeEmpty())
         , fFillType(GrPathRendering::kWinding_FillType)
 #ifdef SK_DEBUG
         , fSkPath(skPath)
         , fStyle(style)
 #endif
     {
     }
 
-    static void ComputeKey(const SkPath& path, const GrStyle& style, GrUniqueKey* key,
-                           bool* outIsVolatile);
+    static void ComputeKey(const GrShape&, GrUniqueKey* key, bool* outIsVolatile);
 
     const SkRect& getBounds() const { return fBounds; }
 
     GrPathRendering::FillType getFillType() const { return fFillType; }
 #ifdef SK_DEBUG
     bool isEqualTo(const SkPath& path, const GrStyle& style) const;
 #endif
 
 protected:
     // Subclass should init these.
     SkRect fBounds;
     GrPathRendering::FillType fFillType;
 #ifdef SK_DEBUG
     SkPath fSkPath;
     GrStyle fStyle;
 #endif
 
 private:
     typedef GrGpuResource INHERITED;
 };
 
 #endif