Move GrFixedClip into src directory

src/gpu/GrClipStackClip.h

 /*
  * Copyright 2016 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 #ifndef GrClipStackClip_DEFINED
 #define GrClipStackClip_DEFINED
 
 #include "GrClip.h"
-
 #include "GrReducedClip.h"
 #include "SkClipStack.h"
 
+class GrPathRenderer;
+class GrTexture;
 class GrTextureProvider;
-class GrPathRenderer;
+class GrUniqueKey;
 
 /**
  * GrClipStackClip can apply a generic SkClipStack to the draw state. It may need to generate an
  * 8-bit alpha clip mask and/or modify the stencil buffer during apply().
  */
 class GrClipStackClip final : public GrClip {
 public:
     GrClipStackClip(const SkClipStack* stack = nullptr, const SkIPoint* origin = nullptr) {
         this->reset(stack, origin);
     }
@@ skipping 43 matching lines @@
                              const GrReducedClip::ElementList& elements);
 
     static GrTexture* CreateCachedMask(int width, int height, const GrUniqueKey& key,
                                        bool renderTarget);
 
     SkIPoint                          fOrigin;
     SkAutoTUnref<const SkClipStack>   fStack;
 };
 
 #endif // GrClipStackClip_DEFINED