Image filters: Make a recursive, forward-mapping bounds traversal.

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 74 matching lines @@
             didProduceResult = true;
         } else {
             bounds.join(srcBounds);
         }
     }
     if (!didProduceResult) {
         return false;
     }
 
     // Apply the crop rect to the union of the inputs' bounds.
-    if (!this->getCropRect().applyTo(bounds, ctx, &bounds)) {
+    this->getCropRect().applyTo(bounds, ctx.ctm(), &bounds);
+    if (!bounds.intersect(ctx.clipBounds())) {
         return false;
     }
 
     const int x0 = bounds.left();
     const int y0 = bounds.top();
 
     // Allocate the destination buffer.
     SkAutoTUnref<SkBaseDevice> dst(proxy->createDevice(bounds.width(), bounds.height()));
     if (nullptr == dst) {
         return false;
@@ skipping 57 matching lines @@
     for (int i = 0; i < this->countInputs(); ++i) {
         SkImageFilter* filter = this->getInput(i);
         str->appendf("%d: (", i);
         filter->toString(str);
         str->appendf(")");
     }
 
     str->append(")");
 }
 #endif