IDL: Don't lose nullable flag when "preprocessing" type

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 2234 matching lines @@
 bool WebGLRenderingContextBase::extensionSupportedAndAllowed(const ExtensionTracker* tracker)
 {
     if (tracker->draft() && !RuntimeEnabledFeatures::webGLDraftExtensionsEnabled())
         return false;
     if (!tracker->supported(this))
         return false;
     return true;
 }
 
 
-PassRefPtrWillBeRawPtr<WebGLExtension> WebGLRenderingContextBase::getExtension(const String& name)
+ScriptValue WebGLRenderingContextBase::getExtension(ScriptState* scriptState, const String& name)
 {
-    if (isContextLost())
-        return nullptr;
+    RefPtrWillBeRawPtr<WebGLExtension> extension;
 
-    for (size_t i = 0; i < m_extensions.size(); ++i) {
-        ExtensionTracker* tracker = m_extensions[i].get();
-        if (tracker->matchesNameWithPrefixes(name)) {
-            if (!extensionSupportedAndAllowed(tracker))
-                return nullptr;
-
-            RefPtrWillBeRawPtr<WebGLExtension> extension = tracker->getExtension(this);
-            if (extension)
-                m_extensionEnabled[extension->name()] = true;
-            return extension.release();
+    if (!isContextLost()) {
+        for (size_t i = 0; i < m_extensions.size(); ++i) {
+            ExtensionTracker* tracker = m_extensions[i].get();
+            if (tracker->matchesNameWithPrefixes(name)) {
+                if (extensionSupportedAndAllowed(tracker)) {
+                    extension = tracker->getExtension(this);
+                    if (extension)
+                        m_extensionEnabled[extension->name()] = true;
+                }
+                break;
+            }
         }
     }
 
-    return nullptr;
+    return ScriptValue(scriptState, toV8(extension, scriptState->context()->Global(), scriptState->isolate()));
 }
 
 ScriptValue WebGLRenderingContextBase::getFramebufferAttachmentParameter(ScriptState* scriptState, GLenum target, GLenum attachment, GLenum pname)
 {
     if (isContextLost() || !validateFramebufferFuncParameters("getFramebufferAttachmentParameter", target, attachment))
         return ScriptValue::createNull(scriptState);
 
     if (!m_framebufferBinding || !m_framebufferBinding->object()) {
         synthesizeGLError(GL_INVALID_OPERATION, "getFramebufferAttachmentParameter", "no framebuffer bound");
         return ScriptValue::createNull(scriptState);
@@ skipping 3753 matching lines @@
     return m_sharedWebGraphicsContext3D ? m_sharedWebGraphicsContext3D->drawingBuffer() : 0;
 }
 #else
 DrawingBuffer* WebGLRenderingContextBase::drawingBuffer() const
 {
     return m_drawingBuffer.get();
 }
 #endif
 
 } // namespace blink