WebGL: add targets for WebGL 2 when check FBO targets

Source/core/html/canvas/WebGL2RenderingContextBase.h

Index: Source/core/html/canvas/WebGL2RenderingContextBase.h
diff --git a/Source/core/html/canvas/WebGL2RenderingContextBase.h b/Source/core/html/canvas/WebGL2RenderingContextBase.h
index 07910d50c938e60f38f585cfb4ed44b34a187936..0ef78d83b14a7bb41f96833fbe7df3a6f6976b8c 100644
--- a/Source/core/html/canvas/WebGL2RenderingContextBase.h
+++ b/Source/core/html/canvas/WebGL2RenderingContextBase.h
@@ -181,6 +181,8 @@ protected:
     bool validateBufferTarget(const char* functionName, GLenum target) override;
     bool validateAndUpdateBufferBindTarget(const char* functionName, GLenum, WebGLBuffer*) override;
     WebGLTexture* validateTextureBinding(const char* functionName, GLenum target, bool useSixEnumsForCubeMap) override;
+    bool validateFramebufferTarget(GLenum target) override;
+    WebGLFramebuffer* getFramebufferBinding(GLenum target) override;
 
     RefPtrWillBeMember<WebGLFramebuffer> m_readFramebufferBinding;
 };