Check for xfer barriers in GrBatch, auto-issue barriers in GrGpu

src/gpu/GrTargetCommands.h

Index: src/gpu/GrTargetCommands.h
diff --git a/src/gpu/GrTargetCommands.h b/src/gpu/GrTargetCommands.h
index a0e65469d39490d155ce8020c52165dbaba7193a..62b26503d37288a4bcac8b72818136302edfe983 100644
--- a/src/gpu/GrTargetCommands.h
+++ b/src/gpu/GrTargetCommands.h
@@ -22,9 +22,7 @@
 
 class GrBufferedDrawTarget;
 
-// TODO: Convert all commands into GrBatch and remove this class. Xferbarrier will just become a
-// batch blocker (when there is overlap) and the xp is responsible for issuing any barrier calls
-// on the backend.
+// TODO: Convert all commands into GrBatch and remove this class.
 class GrTargetCommands : ::SkNoncopyable {
 public:
     GrTargetCommands(GrGpu* gpu)
@@ -42,7 +40,6 @@ public:
             kDrawPath_CmdType          = 5,
             kDrawPaths_CmdType         = 6,
             kDrawBatch_CmdType         = 7,
-            kXferBarrier_CmdType       = 8,
         };
 
         Cmd(CmdType type)
@@ -83,8 +80,6 @@ private:
 
     typedef GrGpu::DrawArgs DrawArgs;
 
-    void recordXferBarrierIfNecessary(const GrPipeline&, GrBufferedDrawTarget*);
-
     // TODO: This can be just a pipeline once paths are in batch, and it should live elsewhere
     struct StateForPathDraw : public SkNVRefCnt<StateForPathDraw> {
         // TODO get rid of the prim proc parameter when we use batch everywhere
@@ -251,20 +246,6 @@ private:
         GrBatchTarget*         fBatchTarget;
     };
 
-    struct XferBarrier : public Cmd {
-        XferBarrier(GrRenderTarget* rt)
-            : Cmd(kXferBarrier_CmdType)
-            , fRenderTarget(rt) {
-        }
-
-        void execute(GrGpu*) override;
-
-        GrXferBarrierType   fBarrierType;
-
-    private:
-        GrPendingIOResource<GrRenderTarget, kWrite_GrIOType> fRenderTarget;
-    };
-
     static const int kCmdBufferInitialSizeInBytes = 8 * 1024;
 
     typedef void* TCmdAlign; // This wouldn't be enough align if a command used long double.