Move GrFixedClip into src directory

src/effects/SkAlphaThresholdFilter.cpp

 /*
  * Copyright 2013 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkAlphaThresholdFilter.h"
 
 #include "SkBitmap.h"
 #include "SkReadBuffer.h"
 #include "SkSpecialImage.h"
 #include "SkWriteBuffer.h"
 #include "SkRegion.h"
 
 #if SK_SUPPORT_GPU
 #include "GrAlphaThresholdFragmentProcessor.h"
 #include "GrContext.h"
 #include "GrDrawContext.h"
+#include "GrFixedClip.h"
 #endif
 
 class SK_API SkAlphaThresholdFilterImpl : public SkImageFilter {
 public:
     SkAlphaThresholdFilterImpl(const SkRegion& region, SkScalar innerThreshold,
                                SkScalar outerThreshold, sk_sp<SkImageFilter> input,
                                const CropRect* cropRect = nullptr);
 
     SK_TO_STRING_OVERRIDE()
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkAlphaThresholdFilterImpl)
@@ skipping 229 matching lines @@
                                           dst);
 }
 
 #ifndef SK_IGNORE_TO_STRING
 void SkAlphaThresholdFilterImpl::toString(SkString* str) const {
     str->appendf("SkAlphaThresholdImageFilter: (");
     str->appendf("inner: %f outer: %f", fInnerThreshold, fOuterThreshold);
     str->append(")");
 }
 #endif