Start using GrGpuCommandBuffer in GrDrawTarget.

src/gpu/batches/GrClearBatch.h

Index: src/gpu/batches/GrClearBatch.h
diff --git a/src/gpu/batches/GrClearBatch.h b/src/gpu/batches/GrClearBatch.h
index ba4b6d6daeabe94baa4ca052a3247026de9d0094..13a709e74d56a8b83f428d3a6ad7b1cfd092c51c 100644
--- a/src/gpu/batches/GrClearBatch.h
+++ b/src/gpu/batches/GrClearBatch.h
@@ -11,6 +11,7 @@
 #include "GrBatch.h"
 #include "GrBatchFlushState.h"
 #include "GrGpu.h"
+#include "GrGpuCommandBuffer.h"
 #include "GrRenderTarget.h"
 
 class GrClearBatch final : public GrBatch {
@@ -58,8 +59,8 @@ private:
 
     void onPrepare(GrBatchFlushState*) override {}
 
-    void onDraw(GrBatchFlushState* state) override {
-        state->gpu()->clear(fRect, fColor, fRenderTarget.get());
+    void onDraw(GrBatchFlushState* state, GrGpuCommandBuffer* buffer) override {
+        buffer->clear(fRect, fColor, fRenderTarget.get());
     }
 
     SkIRect                                                 fRect;
@@ -99,8 +100,8 @@ private:
 
     void onPrepare(GrBatchFlushState*) override {}
 
-    void onDraw(GrBatchFlushState* state) override {
-        state->gpu()->clearStencilClip(fRect, fInsideClip, fRenderTarget.get());
+    void onDraw(GrBatchFlushState* state, GrGpuCommandBuffer* buffer) override {
+        buffer->clearStencilClip(fRect, fInsideClip, fRenderTarget.get());
     }
 
     SkIRect                                                 fRect;