Split GrDrawBatch and GrVertexBatch into their own files

src/gpu/batches/GrDrawBatch.h

+/*
+ * Copyright 2015 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#ifndef GrDrawBatch_DEFINED
+#define GrDrawBatch_DEFINED
+
+#include "GrBatch.h"
+#include "GrPipeline.h"
+
+struct GrInitInvariantOutput;
+
+/**
+ * Base class for GrBatches that draw. These batches have a GrPipeline installed by GrDrawTarget.
+ */
+class GrDrawBatch : public GrBatch {
+public:
+    GrDrawBatch();
+    ~GrDrawBatch() override;
+
+    virtual void getInvariantOutputColor(GrInitInvariantOutput* out) const = 0;
+    virtual void getInvariantOutputCoverage(GrInitInvariantOutput* out) const = 0;
+
+    const GrPipeline* pipeline() const {
+        SkASSERT(fPipelineInstalled);
+        return reinterpret_cast<const GrPipeline*>(fPipelineStorage.get());
+    }
+
+    bool installPipeline(const GrPipeline::CreateArgs&);
+
+    // TODO no GrPrimitiveProcessors yet read fragment position
+    bool willReadFragmentPosition() const { return false; }
+
+private:
+    /**
+     * initBatchTracker is a hook for the some additional overrides / optimization possibilities
+     * from the GrXferProcessor.
+     */
+    virtual void initBatchTracker(const GrPipelineOptimizations&) = 0;
+
+    SkAlignedSTStorage<1, GrPipeline>   fPipelineStorage;
+    bool                                fPipelineInstalled;
+    typedef GrBatch INHERITED;
+};
+
+#endif