Revert of Consolidate GPU buffer implementations

src/gpu/vk/GrVkVertexBuffer.h

Index: src/gpu/vk/GrVkVertexBuffer.h
diff --git a/src/gpu/vk/GrVkVertexBuffer.h b/src/gpu/vk/GrVkVertexBuffer.h
index 7786f6275c59038904c051b0fff8f79fcb3769bd..82f00597b71fbc086b13f9116999f171db3558a7 100644
--- a/src/gpu/vk/GrVkVertexBuffer.h
+++ b/src/gpu/vk/GrVkVertexBuffer.h
@@ -8,13 +8,13 @@
 #ifndef GrVkVertexBuffer_DEFINED
 #define GrVkVertexBuffer_DEFINED
 
-#include "GrBuffer.h"
+#include "GrVertexBuffer.h"
 #include "GrVkBuffer.h"
 #include "vk/GrVkInterface.h"
 
 class GrVkGpu;
 
-class GrVkVertexBuffer : public GrBuffer, public GrVkBuffer {
+class GrVkVertexBuffer : public GrVertexBuffer, public GrVkBuffer {
 public:
     static GrVkVertexBuffer* Create(GrVkGpu* gpu, size_t size, bool dynamic);
 
@@ -26,13 +26,13 @@
     GrVkVertexBuffer(GrVkGpu* gpu, const GrVkBuffer::Desc& desc,
                      const GrVkBuffer::Resource* resource);
 
-    void onMap() override;
+    void* onMap() override;
     void onUnmap() override;
     bool onUpdateData(const void* src, size_t srcSizeInBytes) override;
 
     GrVkGpu* getVkGpu() const;
 
-    typedef GrBuffer INHERITED;
+    typedef GrVertexBuffer INHERITED;
 };
 
 #endif