Add optional data parameter to createBuffer

src/gpu/gl/GrGLGpu.h

Index: src/gpu/gl/GrGLGpu.h
diff --git a/src/gpu/gl/GrGLGpu.h b/src/gpu/gl/GrGLGpu.h
index 738d046450d85d61db88c47edcd06cac7d1bf811..00ceb85241dbce711ea88bba3786392d4275ff51 100644
--- a/src/gpu/gl/GrGLGpu.h
+++ b/src/gpu/gl/GrGLGpu.h
@@ -132,7 +132,8 @@ private:
                                          GrGpuResource::LifeCycle lifeCycle,
                                          const SkTArray<GrMipLevel>& texels) override;
 
-    GrBuffer* onCreateBuffer(size_t size, GrBufferType intendedType, GrAccessPattern) override;
+    GrBuffer* onCreateBuffer(size_t size, GrBufferType intendedType, GrAccessPattern,
+                             const void* data) override;
     GrTexture* onWrapBackendTexture(const GrBackendTextureDesc&, GrWrapOwnership) override;
     GrRenderTarget* onWrapBackendRenderTarget(const GrBackendRenderTargetDesc&,
                                               GrWrapOwnership) override;