Switch SkBlurImageFilter over to new onFilterImage interface

src/core/SkSpecialImage.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 "SkSpecialImage.h"
 
 #if SK_SUPPORT_GPU
 #include "GrTexture.h"
@@ skipping 307 matching lines @@
     void onDraw(SkCanvas* canvas, SkScalar x, SkScalar y, const SkPaint* paint) const override {
         SkRect dst = SkRect::MakeXYWH(x, y,
                                       this->subset().width(), this->subset().height());
 
         canvas->drawBitmapRect(fBitmap, this->subset(),
                                dst, paint, SkCanvas::kStrict_SrcRectConstraint);
     }
 
     bool onPeekPixels(SkPixmap* pixmap) const override {
         const SkImageInfo info = fBitmap.info();
-        if ((kUnknown_SkColorType == info.colorType()) || !fBitmap.getPixels()) {
+
+        if (kUnknown_SkColorType == info.colorType()) {
             return false;
         }
 
+        if (!fBitmap.peekPixels(pixmap)) {
+            fBitmap.lockPixels();
+        }
+
         return fBitmap.peekPixels(pixmap);
     }
 
     bool getBitmapDeprecated(SkBitmap* result) const override {
         *result = fBitmap;
         return true;
     }
 
     bool testingOnlyOnGetROPixels(SkBitmap* result) const override {
         *result = fBitmap;
@@ skipping 193 matching lines @@
 
 sk_sp<SkSpecialImage> SkSpecialImage::MakeFromGpu(SkImageFilter::Proxy* proxy,
                                                   const SkIRect& subset,
                                                   uint32_t uniqueID,
                                                   GrTexture* tex,
                                                   SkAlphaType at) {
     return nullptr;
 }
 
 #endif