Revert of Moving SkBlurImageFilter into core

include/core/SkImageFilter.h

 /*
  * Copyright 2011 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef SkImageFilter_DEFINED
 #define SkImageFilter_DEFINED
 
@@ skipping 134 matching lines @@
      */
     bool isColorFilterNode(SkColorFilter** filterPtr) const {
         return this->onIsColorFilterNode(filterPtr);
     }
 
     // DEPRECATED : use isColorFilterNode() instead
     bool asColorFilter(SkColorFilter** filterPtr) const {
         return this->isColorFilterNode(filterPtr);
     }
 
-    static sk_sp<SkImageFilter> MakeBlur(SkScalar sigmaX, SkScalar sigmaY,
-                                         sk_sp<SkImageFilter> input,
-                                         const CropRect* cropRect = nullptr);
-
     /**
      *  Returns true (and optionally returns a ref'd filter) if this imagefilter can be completely
      *  replaced by the returned colorfilter. i.e. the two effects will affect drawing in the
      *  same way.
      */
     bool asAColorFilter(SkColorFilter** filterPtr) const;
 
     /**
      *  Returns the number of inputs this filter will accept (some inputs can
      *  be NULL).
@@ skipping 57 matching lines @@
 #ifdef SK_SUPPORT_LEGACY_IMAGEFILTER_PTR
     static SkImageFilter* CreateMatrixFilter(const SkMatrix& matrix,
                                              SkFilterQuality filterQuality,
                                              SkImageFilter* input = nullptr) {
         return MakeMatrixFilter(matrix, filterQuality, sk_ref_sp<SkImageFilter>(input)).release();
     }
 #endif
 
     SK_TO_STRING_PUREVIRT()
     SK_DEFINE_FLATTENABLE_TYPE(SkImageFilter)
-    SK_DECLARE_FLATTENABLE_REGISTRAR_GROUP()
 
 protected:
     class Common {
     public:
         /**
          *  Attempt to unflatten the cropRect and the expected number of input filters.
          *  If any number of input filters is valid, pass -1.
          *  If this fails (i.e. corrupt buffer or contents) then return false and common will
          *  be left uninitialized.
          *  If this returns true, then inputCount() is the number of found input filters, each
@@ skipping 157 matching lines @@
  */
 #define SK_IMAGEFILTER_UNFLATTEN_COMMON(localVar, expectedCount)    \
     Common localVar;                                                \
     do {                                                            \
         if (!localVar.unflatten(buffer, expectedCount)) {           \
             return NULL;                                            \
         }                                                           \
     } while (0)
 
 #endif