More natural way to serialize GPU tasks and tests.

gyp/dm.gypi

 # GYP for "dm" (Diamond Master, a.k.a Dungeon master, a.k.a GM 2).
 {
   'include_dirs': [
     '../dm',
     '../gm',
     '../tests',
     '../src/images',
     '../src/lazy',
     '../src/core',
     '../src/effects',
@@ skipping 12 matching lines @@
     'tools.gyp:sk_tool_utils',
     'tools.gyp:timer',
   ],
   'includes': [
     'gmslides.gypi',
     'pathops_unittest.gypi',
     'tests.gypi',
   ],
   'sources': [
     '../dm/DM.cpp',
-    '../dm/DMGpuSupport.cpp',
     '../dm/DMSrcSink.cpp',
     '../dm/DMJsonWriter.cpp',
     '../gm/gm.cpp',
 
     '../src/pipe/utils/SamplePipeControllers.cpp',
     '../src/utils/debugger/SkDebugCanvas.cpp',
     '../src/utils/debugger/SkDrawCommand.cpp',
     '../src/utils/debugger/SkObjectParser.cpp',
   ],
   'conditions': [
     [ 'skia_gpu == 1', {
       'dependencies': [ 'gputest.gyp:skgputest' ],
     }],
   ],
 }