WebGL 2: a small fix to support mipmap level in framebufferTexture2D

Source/core/html/canvas/WebGLRenderingContextBase.cpp

 /*
  * Copyright (C) 2009 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 2021 matching lines @@
         webContext()->framebufferRenderbuffer(target, attachment, renderbuffertarget, bufferObject);
     }
     m_framebufferBinding->setAttachmentForBoundFramebuffer(attachment, buffer);
     applyStencilTest();
 }
 
 void WebGLRenderingContextBase::framebufferTexture2D(GLenum target, GLenum attachment, GLenum textarget, WebGLTexture* texture, GLint level)
 {
     if (isContextLost() || !validateFramebufferFuncParameters("framebufferTexture2D", target, attachment))
         return;
-    if (level) {
+    if (isWebGL2OrHigher()) {
+        if (!validateTexFuncLevel("framebufferTexture2D", textarget, level))
+            return;
+    } else if (level) {
         synthesizeGLError(GL_INVALID_VALUE, "framebufferTexture2D", "level not 0");
         return;
     }
     if (texture && !texture->validate(contextGroup(), this)) {
         synthesizeGLError(GL_INVALID_OPERATION, "framebufferTexture2D", "no texture or texture not from this context");
         return;
     }
     // Don't allow the default framebuffer to be mutated; all current
     // implementations use an FBO internally in place of the default
     // FBO.
@@ skipping 4159 matching lines @@
 
     return totalBytesPerPixel;
 }
 
 DrawingBuffer* WebGLRenderingContextBase::drawingBuffer() const
 {
     return m_drawingBuffer.get();
 }
 
 } // namespace blink