Fix WebGL context restoration logic. The retry mechanism was broken when the ownership of the WebGr…

Source/core/html/canvas/WebGLRenderingContext.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 72 matching lines @@
         defaultAttrs = WebGLContextAttributes::create();
         attrs = defaultAttrs.get();
     }
     blink::WebGraphicsContext3D::Attributes attributes = attrs->attributes(document.topDocument().url().string(), settings);
     OwnPtr<blink::WebGraphicsContext3D> context = adoptPtr(blink::Platform::current()->createOffscreenGraphicsContext3D(attributes, 0));
     if (!context || !context->makeContextCurrent()) {
         canvas->dispatchEvent(WebGLContextEvent::create(EventTypeNames::webglcontextcreationerror, false, true, "Could not create a WebGL context."));
         return nullptr;
     }
 
-    Extensions3DUtil extensionsUtil(context.get());
-    if (extensionsUtil.supportsExtension("GL_EXT_debug_marker"))
+    OwnPtr<Extensions3DUtil> extensionsUtil = Extensions3DUtil::create(context.get());
+    if (!extensionsUtil)
+        return nullptr;
+    if (extensionsUtil->supportsExtension("GL_EXT_debug_marker"))
         context->pushGroupMarkerEXT("WebGLRenderingContext");
 
     OwnPtr<WebGLRenderingContext> renderingContext = adoptPtr(new WebGLRenderingContext(canvas, context.release(), attrs));
     renderingContext->registerContextExtensions();
     renderingContext->suspendIfNeeded();
 
     if (!renderingContext->m_drawingBuffer) {
         canvas->dispatchEvent(WebGLContextEvent::create(EventTypeNames::webglcontextcreationerror, false, true, "Could not create a WebGL context."));
         return nullptr;
     }
@@ skipping 38 matching lines @@
     registerExtension<EXTFragDepth>(m_extFragDepth, DraftExtension);
     registerExtension<EXTShaderTextureLOD>(m_extShaderTextureLOD, DraftExtension);
     registerExtension<WebGLCompressedTextureETC1>(m_webglCompressedTextureETC1, DraftExtension);
 
     // Register privileged extensions.
     registerExtension<WebGLDebugRendererInfo>(m_webglDebugRendererInfo, WebGLDebugRendererInfoExtension);
     registerExtension<WebGLDebugShaders>(m_webglDebugShaders, PrivilegedExtension);
 }
 
 } // namespace WebCore