DM: also run benches once.

dm/DMGpuTask.h

Index: dm/DMGpuTask.h
diff --git a/dm/DMGpuTask.h b/dm/DMGpuTask.h
index 1380e443d46e93ed12ac6f6e69878b84110d0d3e..f74950c0880eca7e6b63331703672a2518a5de4f 100644
--- a/dm/DMGpuTask.h
+++ b/dm/DMGpuTask.h
@@ -17,12 +17,11 @@ namespace DM {
 
 class GpuTask : public Task {
 public:
-    GpuTask(const char* name,
+    GpuTask(const char* config,
             Reporter*,
             TaskRunner*,
             const Expectations&,
             skiagm::GMRegistry::Factory,
-            SkColorType,
             GrContextFactory::GLContextType,
             int sampleCount);
 
@@ -32,11 +31,9 @@ public:
     virtual SkString name() const SK_OVERRIDE { return fName; }
 
 private:
-    TaskRunner* fTaskRunner;
     SkAutoTDelete<skiagm::GM> fGM;
     const SkString fName;
     const Expectations& fExpectations;
-    const SkColorType fColorType;
     const GrContextFactory::GLContextType fContextType;
     const int fSampleCount;
 };