Implement support for a Context parameter in image filters

src/effects/SkMergeImageFilter.cpp

 /*
  * Copyright 2012 The Android Open Source Project
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkMergeImageFilter.h"
 #include "SkCanvas.h"
 #include "SkDevice.h"
@@ skipping 48 matching lines @@
 }
 
 SkMergeImageFilter::~SkMergeImageFilter() {
 
     if (fModes != SkTCast<uint8_t*>(fStorage)) {
         sk_free(fModes);
     }
 }
 
 bool SkMergeImageFilter::onFilterImage(Proxy* proxy, const SkBitmap& src,
-                                       const SkMatrix& ctm,
+                                       const Context& ctx,
                                        SkBitmap* result, SkIPoint* offset) const {
     if (countInputs() < 1) {
         return false;
     }
 
     SkIRect bounds;
     src.getBounds(&bounds);
-    if (!this->applyCropRect(&bounds, ctm)) {
+    if (!this->applyCropRect(&bounds, ctx.ctm())) {
         return false;
     }
 
     const int x0 = bounds.left();
     const int y0 = bounds.top();
 
     SkAutoTUnref<SkBaseDevice> dst(proxy->createDevice(bounds.width(), bounds.height()));
     if (NULL == dst) {
         return false;
     }
     SkCanvas canvas(dst);
     SkPaint paint;
 
     int inputCount = countInputs();
     for (int i = 0; i < inputCount; ++i) {
         SkBitmap tmp;
         const SkBitmap* srcPtr;
         SkIPoint pos = SkIPoint::Make(0, 0);
         SkImageFilter* filter = getInput(i);
         if (filter) {
-            if (!filter->filterImage(proxy, src, ctm, &tmp, &pos)) {
+            if (!filter->filterImage(proxy, src, ctx, &tmp, &pos)) {
                 return false;
             }
             srcPtr = &tmp;
         } else {
             srcPtr = &src;
         }
 
         if (fModes) {
             paint.setXfermodeMode((SkXfermode::Mode)fModes[i]);
         } else {
@@ skipping 28 matching lines @@
         if (buffer.validate(buffer.getArrayCount() == size) &&
             buffer.readByteArray(fModes, size)) {
             for (int i = 0; i < nbInputs; ++i) {
                 buffer.validate(SkIsValidMode((SkXfermode::Mode)fModes[i]));
             }
         }
     } else {
         fModes = 0;
     }
 }