Use visitDOMWrapper to preserve WebGL JS object wrappers

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

Index: third_party/WebKit/Source/modules/webgl/WebGLRenderingContextBase.h
diff --git a/third_party/WebKit/Source/modules/webgl/WebGLRenderingContextBase.h b/third_party/WebKit/Source/modules/webgl/WebGLRenderingContextBase.h
index 4c5824f71f469208ecf09c2479290a9cc46f2047..756e0c6608de48583da2c8385c74110d0ab2f159 100644
--- a/third_party/WebKit/Source/modules/webgl/WebGLRenderingContextBase.h
+++ b/third_party/WebKit/Source/modules/webgl/WebGLRenderingContextBase.h
@@ -27,7 +27,6 @@
 #define WebGLRenderingContextBase_h
 
 #include "bindings/core/v8/Nullable.h"
-#include "bindings/core/v8/ScopedPersistent.h"
 #include "bindings/core/v8/ScriptState.h"
 #include "bindings/core/v8/ScriptValue.h"
 #include "bindings/core/v8/ScriptWrappable.h"
@@ -150,12 +149,12 @@ public:
     int drawingBufferHeight() const;
 
     void activeTexture(GLenum texture);
-    void attachShader(ScriptState*, WebGLProgram*, WebGLShader*);
+    void attachShader(WebGLProgram*, WebGLShader*);
     void bindAttribLocation(WebGLProgram*, GLuint index, const String& name);
-    void bindBuffer(ScriptState*, GLenum target, WebGLBuffer*);
-    virtual void bindFramebuffer(ScriptState*, GLenum target, WebGLFramebuffer*);
-    void bindRenderbuffer(ScriptState*, GLenum target, WebGLRenderbuffer*);
-    void bindTexture(ScriptState*, GLenum target, WebGLTexture*);
+    void bindBuffer(GLenum target, WebGLBuffer*);
+    virtual void bindFramebuffer(GLenum target, WebGLFramebuffer*);
+    void bindRenderbuffer(GLenum target, WebGLRenderbuffer*);
+    void bindTexture(GLenum target, WebGLTexture*);
     void blendColor(GLfloat red, GLfloat green, GLfloat blue, GLfloat alpha);
     void blendEquation(GLenum mode);
     void blendEquationSeparate(GLenum modeRGB, GLenum modeAlpha);
@@ -201,7 +200,7 @@ public:
     void depthFunc(GLenum);
     void depthMask(GLboolean);
     void depthRange(GLfloat zNear, GLfloat zFar);
-    void detachShader(ScriptState*, WebGLProgram*, WebGLShader*);
+    void detachShader(WebGLProgram*, WebGLShader*);
     void disable(GLenum cap);
     void disableVertexAttribArray(GLuint index);
     void drawArrays(GLenum mode, GLint first, GLsizei count);
@@ -214,8 +213,8 @@ public:
     void enableVertexAttribArray(GLuint index);
     void finish();
     void flush();
-    void framebufferRenderbuffer(ScriptState*, GLenum target, GLenum attachment, GLenum renderbuffertarget, WebGLRenderbuffer*);
-    void framebufferTexture2D(ScriptState*, GLenum target, GLenum attachment, GLenum textarget, WebGLTexture*, GLint level);
+    void framebufferRenderbuffer(GLenum target, GLenum attachment, GLenum renderbuffertarget, WebGLRenderbuffer*);
+    void framebufferTexture2D(GLenum target, GLenum attachment, GLenum textarget, WebGLTexture*, GLint level);
     void frontFace(GLenum mode);
     void generateMipmap(GLenum target);
 
@@ -332,7 +331,7 @@ public:
     void uniformMatrix4fv(const WebGLUniformLocation*, GLboolean transpose, DOMFloat32Array* value);
     void uniformMatrix4fv(const WebGLUniformLocation*, GLboolean transpose, Vector<GLfloat>& value);
 
-    void useProgram(ScriptState*, WebGLProgram*);
+    void useProgram(WebGLProgram*);
     void validateProgram(WebGLProgram*);
 
     void vertexAttrib1f(GLuint index, GLfloat x);
@@ -347,7 +346,7 @@ public:
     void vertexAttrib4f(GLuint index, GLfloat x, GLfloat y, GLfloat z, GLfloat w);
     void vertexAttrib4fv(GLuint index, const DOMFloat32Array* values);
     void vertexAttrib4fv(GLuint index, const Vector<GLfloat>& values);
-    void vertexAttribPointer(ScriptState*, GLuint index, GLint size, GLenum type, GLboolean normalized,
+    void vertexAttribPointer(GLuint index, GLint size, GLenum type, GLboolean normalized,
         GLsizei stride, long long offset);
 
     void vertexAttribDivisorANGLE(GLuint index, GLuint divisor);
@@ -435,6 +434,8 @@ protected:
     friend class WebGLVertexArrayObjectBase;
     friend class ScopedTexture2DRestorer;
     friend class ScopedFramebufferRestorer;
+    // To allow V8WebGL[2]RenderingContext to call visitChildDOMWrappers.
+    friend class V8WebGLRenderingContext;
 
     WebGLRenderingContextBase(HTMLCanvasElement*, std::unique_ptr<WebGraphicsContext3DProvider>, const CanvasContextCreationAttributes&, unsigned);
     WebGLRenderingContextBase(OffscreenCanvas*, std::unique_ptr<WebGraphicsContext3DProvider>, const CanvasContextCreationAttributes&, unsigned);
@@ -481,6 +482,8 @@ protected:
     // Restore the client unpack parameters.
     virtual void restoreUnpackParameters();
 
+    virtual void visitChildDOMWrappers(v8::Isolate*, const v8::Persistent<v8::Object>&);
+
     PassRefPtr<Image> drawImageIntoBuffer(PassRefPtr<Image>, int width, int height, const char* functionName);
 
     PassRefPtr<Image> videoFrameToImage(HTMLVideoElement*);
@@ -512,8 +515,7 @@ protected:
 
     Member<WebGLVertexArrayObjectBase> m_defaultVertexArrayObject;
     Member<WebGLVertexArrayObjectBase> m_boundVertexArrayObject;
-    bool m_preservedDefaultVAOObjectWrapper;
-    void setBoundVertexArrayObject(ScriptState*, WebGLVertexArrayObjectBase*);
+    void setBoundVertexArrayObject(WebGLVertexArrayObjectBase*);
 
     enum VertexAttribValueType {
         Float32ArrayType,
@@ -619,6 +621,9 @@ protected:
         virtual const char* extensionName() const = 0;
         virtual void loseExtension(bool) = 0;
 
+        // This is only used for keeping the JS wrappers of extensions alive.
+        virtual WebGLExtension* getExtensionObjectIfAlreadyEnabled() = 0;
+
         DEFINE_INLINE_VIRTUAL_TRACE() { }
 
     private:
@@ -663,6 +668,11 @@ protected:
             }
         }
 
+        WebGLExtension* getExtensionObjectIfAlreadyEnabled() override
+        {
+            return m_extension;
+        }
+
         DEFINE_INLINE_VIRTUAL_TRACE()
         {
             visitor->trace(m_extension);
@@ -1055,38 +1065,6 @@ protected:
 
     virtual void renderbufferStorageImpl(GLenum target, GLsizei samples, GLenum internalformat, GLsizei width, GLsizei height, const char* functionName);
 
-    // Ensures that the JavaScript wrappers for objects that are
-    // latched into the context's state, or which are implicitly
-    // linked together (like programs and their attached shaders), are
-    // not garbage collected before they should be.
-    ScopedPersistent<v8::Array> m_wrappersOf2DTextures;
-    ScopedPersistent<v8::Array> m_wrappersOf2DArrayTextures;
-    ScopedPersistent<v8::Array> m_wrappersOf3DTextures;
-    ScopedPersistent<v8::Array> m_cubeMapTextureWrappers;
-    ScopedPersistent<v8::Array> m_extensionWrappers;
-
-    // The "catch-all" array for the rest of the preserved object
-    // wrappers. The enum below defines how the indices in this array
-    // are used.
-    enum PreservedWrapperIndex {
-        PreservedArrayBuffer,
-        PreservedElementArrayBuffer,
-        PreservedFramebuffer,
-        PreservedProgram,
-        PreservedRenderbuffer,
-        PreservedDefaultVAO,
-        PreservedVAO,
-        PreservedTransformFeedback,
-    };
-    ScopedPersistent<v8::Array> m_miscWrappers;
-
-    static void preserveObjectWrapper(ScriptState*, ScriptWrappable* sourceObject, v8::Local<v8::String> hiddenValueName, ScopedPersistent<v8::Array>* persistentCache, uint32_t index, ScriptWrappable* targetObject);
-
-    // Called to lazily instantiate the wrapper for the default VAO
-    // during calls to bindBuffer and vertexAttribPointer (from
-    // JavaScript).
-    void maybePreserveDefaultVAOObjectWrapper(ScriptState*);
-
     friend class WebGLStateRestorer;
     friend class WebGLRenderingContextEvictionManager;