Move GrFixedClip into src directory

src/gpu/GrClipStackClip.cpp

 /*
  * Copyright 2016 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "GrClipStackClip.h"
 
 #include "GrAppliedClip.h"
 #include "GrDrawingManager.h"
 #include "GrDrawContextPriv.h"
+#include "GrFixedClip.h"
 #include "GrGpuResourcePriv.h"
 #include "GrRenderTargetPriv.h"
 #include "GrStencilAttachment.h"
 #include "GrSWMaskHelper.h"
 #include "effects/GrConvexPolyEffect.h"
 #include "effects/GrRRectEffect.h"
 #include "effects/GrTextureDomain.h"
 
 typedef SkClipStack::Element Element;
 typedef GrReducedClip::InitialState InitialState;
@@ skipping 759 matching lines @@
     sk_sp<GrTexture> result(texProvider->createApproxTexture(desc));
     if (!result) {
         return nullptr;
     }
     result->resourcePriv().setUniqueKey(key);
 
     helper.toTexture(result.get());
 
     return result;
 }