Change device factories to take SkImageInfo instead of SkBitmap::Config

dm/DMCpuTask.h

 #ifndef DMCpuTask_DEFINED
 #define DMCpuTask_DEFINED
 
 #include "DMExpectations.h"
 #include "DMReporter.h"
 #include "DMTask.h"
 #include "DMTaskRunner.h"
 #include "SkBitmap.h"
 #include "SkString.h"
 #include "SkTemplates.h"
 #include "gm.h"
 
 // This is the main entry point for drawing GMs with the CPU.  Commandline
 // flags control whether this kicks off various comparison tasks when done.
 
 namespace DM {
 
 class CpuTask : public Task {
 public:
     CpuTask(const char* name,
             Reporter*,
             TaskRunner*,
             const Expectations&,
             skiagm::GMRegistry::Factory,
-            SkBitmap::Config);
+            SkColorType);
 
     virtual void draw() SK_OVERRIDE;
     virtual bool usesGpu() const SK_OVERRIDE { return false; }
     virtual bool shouldSkip() const SK_OVERRIDE;
     virtual SkString name() const SK_OVERRIDE { return fName; }
 
 private:
     skiagm::GMRegistry::Factory fGMFactory;
     SkAutoTDelete<skiagm::GM> fGM;
     const SkString fName;
     const Expectations& fExpectations;
-    const SkBitmap::Config fConfig;
+    const SkColorType fColorType;
 };
 
 }  // namespace DM
 
 #endif // DMCpuTask_DEFINED