Easy DM TODO: LazyDecodeBitmap does not help (or hinder).

BUG=skia:3255

Review URL: https://codereview.chromium.org/859303003

dm/DMSrcSink.cpp

@@ -240,7 +240,6 @@ Error ViaPipe::draw(const Src& src, SkBitmap* bitmap, SkWStream* stream) const {
 
         Error draw(SkCanvas* canvas) const SK_OVERRIDE {
             SkISize size = this->size();
-            // TODO: is DecodeMemory really required? Might help RAM usage to be lazy if we can.
             PipeController controller(canvas, &SkImageDecoder::DecodeMemory);
             SkGPipeWriter pipe;
             const uint32_t kFlags = 0; // We mirror SkDeferredCanvas, which doesn't use any flags.

gyp/dm.gypi

@@ -39,7 +39,6 @@
     '../src/utils/debugger/SkDebugCanvas.cpp',
     '../src/utils/debugger/SkDrawCommand.cpp',
     '../src/utils/debugger/SkObjectParser.cpp',
-    '../tools/LazyDecodeBitmap.cpp',
   ],
   'conditions': [
     [ 'skia_gpu == 1', {