SkRasterPipeline in SkArenaAlloc

Bug: skia:6673

Change-Id: Ia2bae4f6a9039a007a10b6b45bcf2f0854bf6e5c
Reviewed-on: https://skia-review.googlesource.com/17794
Reviewed-by: Mike Reed <reed@google.com>
Commit-Queue: Mike Klein <mtklein@chromium.org>
diff --git a/src/codec/SkWebpCodec.cpp b/src/codec/SkWebpCodec.cpp
index b2e1e64..829ebb8 100644
--- a/src/codec/SkWebpCodec.cpp
+++ b/src/codec/SkWebpCodec.cpp
@@ -338,7 +338,7 @@
                        bool needsSrgbToLinear, SkAlphaType at,
                        int width) {
     // Setup conversion from the source and dest, which will be the same.
-    SkRasterPipeline convert_to_linear_premul;
+    SkRasterPipeline_<256> convert_to_linear_premul;
     if (needsSrgbToLinear) {
         convert_to_linear_premul.append_from_srgb(at);
     }
@@ -347,7 +347,7 @@
         convert_to_linear_premul.append(SkRasterPipeline::premul);
     }
 
-    SkRasterPipeline p;
+    SkRasterPipeline_<256> p;
     SkRasterPipeline::StockStage load_dst, store_dst;
     pick_memory_stages(dstCT, &load_dst, &store_dst);