Add offset arguments to readPixels and compressedTex* per WebGL 2.0 spec.

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

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 typedef long long GLint64;
 typedef unsigned long long GLuint64;
 
 [
     NoInterfaceObject,
 ] interface WebGL2RenderingContextBase {
@@ skipping 318 matching lines @@
     void texSubImage3D(GLenum target, GLint level, GLint xoffset, GLint yoffset, GLint zoffset, GLsizei width, GLsizei height, GLsizei depth, GLenum format, GLenum type, ArrayBufferView pixels, optional GLuint srcOffset = 0);
 
     // TODO(zmo): Obsolete, remove after WebGL2 conformance tests are updated.
     void texSubImage3D(GLenum target, GLint level, GLint xoffset, GLint yoffset, GLint zoffset, GLenum format, GLenum type, ImageData data);
     [RaisesException] void texSubImage3D(GLenum target, GLint level, GLint xoffset, GLint yoffset, GLint zoffset, GLenum format, GLenum type, HTMLImageElement image);
     [RaisesException] void texSubImage3D(GLenum target, GLint level, GLint xoffset, GLint yoffset, GLint zoffset, GLenum format, GLenum type, HTMLCanvasElement canvas);
     [RaisesException] void texSubImage3D(GLenum target, GLint level, GLint xoffset, GLint yoffset, GLint zoffset, GLenum format, GLenum type, HTMLVideoElement video);
     [RaisesException] void texSubImage3D(GLenum target, GLint level, GLint xoffset, GLint yoffset, GLint zoffset, GLenum format, GLenum type, ImageBitmap bitmap);
 
     void copyTexSubImage3D(GLenum target, GLint level, GLint xoffset, GLint yoffset, GLint zoffset, GLint x, GLint y, GLsizei width, GLsizei height);
-    void compressedTexImage3D(GLenum target, GLint level, GLenum internalformat, GLsizei width, GLsizei height, GLsizei depth, GLint border, ArrayBufferView data);
-    void compressedTexSubImage3D(GLenum target, GLint level, GLint xoffset, GLint yoffset, GLint zoffset, GLsizei width, GLsizei height, GLsizei depth, GLenum format, ArrayBufferView data);
+
+    void compressedTexImage2D(GLenum target, GLint level, GLenum internalformat,
+                              GLsizei width, GLsizei height, GLint border,
+                              ArrayBufferView data, GLuint srcOffset,
+                              optional GLuint srcLengthOverride = 0);
+    void compressedTexSubImage2D(GLenum target, GLint level, GLint xoffset, GLint yoffset,
+                                 GLsizei width, GLsizei height, GLenum format,
+                                 ArrayBufferView data, GLuint srcOffset,
+                                 optional GLuint srcLengthOverride = 0);
+    void compressedTexImage3D(GLenum target, GLint level, GLenum internalformat, GLsizei width, GLsizei height, GLsizei depth, GLint border, ArrayBufferView data, optional GLuint srcOffset = 0, optional GLuint srcLengthOverride = 0);
+    void compressedTexSubImage3D(GLenum target, GLint level, GLint xoffset, GLint yoffset, GLint zoffset, GLsizei width, GLsizei height, GLsizei depth, GLenum format, ArrayBufferView data, optional GLuint srcOffset = 0, optional GLuint srcLengthOverride = 0);
 
     /* Programs and shaders */
     GLint getFragDataLocation(WebGLProgram? program, DOMString name);
 
     /* Uniforms and attributes */
     void uniform1ui(WebGLUniformLocation? location, GLuint v0);
     void uniform2ui(WebGLUniformLocation? location, GLuint v0, GLuint v1);
     void uniform3ui(WebGLUniformLocation? location, GLuint v0, GLuint v1, GLuint v2);
     void uniform4ui(WebGLUniformLocation? location, GLuint v0, GLuint v1, GLuint v2, GLuint v3);
     void uniform1uiv(WebGLUniformLocation? location, [FlexibleArrayBufferView] Uint32Array v);
@@ skipping 91 matching lines @@
     DOMString? getActiveUniformBlockName(WebGLProgram? program, GLuint uniformBlockIndex);
     void uniformBlockBinding(WebGLProgram? program, GLuint uniformBlockIndex, GLuint uniformBlockBinding);
 
     /* Vertex Array Objects */
     WebGLVertexArrayObject createVertexArray();
     void deleteVertexArray(WebGLVertexArrayObject? vertexArray);
     GLboolean isVertexArray(WebGLVertexArrayObject? vertexArray);
     void bindVertexArray(WebGLVertexArrayObject? vertexArray);
 
     /* Reading */
+    void readPixels(GLint x, GLint y, GLsizei width, GLsizei height, GLenum format, GLenum type, ArrayBufferView dstData, GLintptr offset);
     void readPixels(GLint x, GLint y, GLsizei width, GLsizei height, GLenum format, GLenum type, GLintptr offset);
 };
 WebGL2RenderingContextBase implements WebGLRenderingContextBase;