Split drawing functionality out of GrContext and into new GrDrawContext

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 "GrDrawContext.h"
 #include "SkAlphaThresholdFilter.h"
 #include "SkBitmap.h"
 #include "SkReadBuffer.h"
 #include "SkWriteBuffer.h"
 #include "SkRegion.h"
 
 class SK_API SkAlphaThresholdFilterImpl : public SkImageFilter {
 public:
     SkAlphaThresholdFilterImpl(const SkRegion& region, SkScalar innerThreshold,
                                SkScalar outerThreshold, SkImageFilter* input);
@@ skipping 259 matching lines @@
         // Add one pixel of border to ensure that clamp mode will be all zeros
         // the outside.
         maskDesc.fWidth = texture->width();
         maskDesc.fHeight = texture->height();
         SkAutoTUnref<GrTexture> maskTexture(context->textureProvider()->refScratchTexture(
             maskDesc, GrTextureProvider::kApprox_ScratchTexMatch));
         if (!maskTexture) {
             return false;
         }
 
-        {
+        GrDrawContext* drawContext = context->drawContext();
+        if (drawContext) {
             GrPaint grPaint;
             grPaint.setPorterDuffXPFactory(SkXfermode::kSrc_Mode);
             SkRegion::Iterator iter(fRegion);
-            context->clear(NULL, 0x0, true, maskTexture->asRenderTarget());
+            drawContext->clear(maskTexture->asRenderTarget(), NULL, 0x0, true);
 
             while (!iter.done()) {
                 SkRect rect = SkRect::Make(iter.rect());
-                context->drawRect(maskTexture->asRenderTarget(), GrClip::WideOpen(), grPaint,
-                                  in_matrix, rect);
+                drawContext->drawRect(maskTexture->asRenderTarget(), GrClip::WideOpen(), grPaint,
+                                      in_matrix, rect);
                 iter.next();
             }
         }
 
         *fp = AlphaThresholdEffect::Create(texture,
                                            maskTexture,
                                            fInnerThreshold,
                                            fOuterThreshold);
     }
     return true;
@@ skipping 70 matching lines @@
 }
 
 #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