implement getBufferSubDataAsync prototype

third_party/WebKit/Source/modules/webgl/WebGL2RenderingContextBase.h

Index: third_party/WebKit/Source/modules/webgl/WebGL2RenderingContextBase.h
diff --git a/third_party/WebKit/Source/modules/webgl/WebGL2RenderingContextBase.h b/third_party/WebKit/Source/modules/webgl/WebGL2RenderingContextBase.h
index 23479a91c40c872683f81e18756676d6259718c6..e03d8f50567ea105f0a48bcc3885fccc8aaf6f2c 100644
--- a/third_party/WebKit/Source/modules/webgl/WebGL2RenderingContextBase.h
+++ b/third_party/WebKit/Source/modules/webgl/WebGL2RenderingContextBase.h
@@ -5,6 +5,7 @@
 #ifndef WebGL2RenderingContextBase_h
 #define WebGL2RenderingContextBase_h
 
+#include "bindings/core/v8/ScriptPromise.h"
 #include "modules/webgl/WebGLExtension.h"
 #include "modules/webgl/WebGLRenderingContextBase.h"
 #include <memory>
@@ -15,6 +16,7 @@ class WebGLTexture;
 
 class WebGLActiveInfo;
 class WebGLBuffer;
+class WebGLGetBufferSubDataAsyncCallback;
 class WebGLProgram;
 class WebGLQuery;
 class WebGLSampler;
@@ -27,6 +29,8 @@ class WebGL2RenderingContextBase : public WebGLRenderingContextBase {
  public:
   ~WebGL2RenderingContextBase() override;
 
+  void destroyContext() override;
+
   /* Buffer objects */
   void bufferData(GLenum, DOMArrayBufferView*, GLenum, GLuint, GLuint);
   void bufferSubData(GLenum, GLintptr, DOMArrayBufferView*, GLuint, GLuint);
@@ -43,6 +47,12 @@ class WebGL2RenderingContextBase : public WebGLRenderingContextBase {
 
   void copyBufferSubData(GLenum, GLenum, long long, long long, long long);
   void getBufferSubData(GLenum, long long, DOMArrayBufferView*, GLuint, GLuint);
+  ScriptPromise getBufferSubDataAsync(ScriptState*,
+                                      GLenum,
+                                      GLintptr,
+                                      DOMArrayBufferView*,
+                                      GLuint,
+                                      GLuint);
 
   /* Framebuffer objects */
   bool validateTexFuncLayer(const char*, GLenum texTarget, GLint layer);
@@ -811,6 +821,29 @@ class WebGL2RenderingContextBase : public WebGLRenderingContextBase {
                                         GLenum target) override;
   bool validateBufferDataUsage(const char* functionName, GLenum usage) override;
 
+  const char* validateGetBufferSubData(const char*,
+                                       GLenum,
+                                       GLintptr,
+                                       DOMArrayBufferView*,
+                                       GLuint,
+                                       GLuint,
+                                       WebGLBuffer**,
+                                       void**,
+                                       long long*);
+  const char* validateGetBufferSubDataBounds(const char*,
+                                             WebGLBuffer*,
+                                             GLintptr,
+                                             long long);
+
+  std::set<WebGLGetBufferSubDataAsyncCallback*>
+      m_getBufferSubDataAsyncCallbacks;
+
+  friend class WebGLGetBufferSubDataAsyncCallback;
+  void registerGetBufferSubDataAsyncCallback(
+      WebGLGetBufferSubDataAsyncCallback*);
+  void unregisterGetBufferSubDataAsyncCallback(
+      WebGLGetBufferSubDataAsyncCallback*);
+
   bool canUseTexImageByGPU(TexImageFunctionID,
                            GLint internalformat,
                            GLenum type) override;