Use variable length key (rather than accumulated matrix) as save layer hoisting key

src/core/SkMultiPictureDraw.cpp

 /*
  * Copyright 2014 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 // Need to include something before #if SK_SUPPORT_GPU so that the Android
 // framework build, which gets its defines from SkTypes rather than a makefile,
 // has the definition before checking it.
@@ skipping 152 matching lines @@
             // Find the layers required by this canvas. It will return atlased
             // layers in the 'recycled' list since they have already been drawn.
             GrLayerHoister::FindLayersToHoist(context, picture, initialMatrix,
                                               clipBounds, &needRendering, &recycled,
                                               rt->numSamples());
 
             GrLayerHoister::DrawLayers(context, needRendering);
 
             GrReplacements replacements;
 
-            GrLayerHoister::ConvertLayersToReplacements(needRendering, &replacements);
-            GrLayerHoister::ConvertLayersToReplacements(recycled, &replacements);
+            GrLayerHoister::ConvertLayersToReplacements(picture, needRendering, &replacements);
+            GrLayerHoister::ConvertLayersToReplacements(picture, recycled, &replacements);
 
             // Render the entire picture using new layers
             GrRecordReplaceDraw(picture, canvas, &replacements, initialMatrix, NULL);
 
             GrLayerHoister::UnlockLayers(context, needRendering);
             GrLayerHoister::UnlockLayers(context, recycled);
 
             needRendering.rewind();
             recycled.rewind();
         } else
 #endif
         {
             canvas->drawPicture(picture, &data.fMatrix, data.fPaint);
         }
     }
 
 #if !defined(SK_IGNORE_GPU_LAYER_HOISTING) && SK_SUPPORT_GPU
     GrLayerHoister::UnlockLayers(context, atlasedNeedRendering);
     GrLayerHoister::UnlockLayers(context, atlasedRecycled);
 #if !GR_CACHE_HOISTED_LAYERS
     GrLayerHoister::PurgeCache(context);
 #endif
 #endif
 }