binding: Changes the association among global-proxy/global/window-instance.

third_party/WebKit/Source/core/frame/DOMWindow.cpp

 // Copyright 2014 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.
 
 #include "core/frame/DOMWindow.h"
 
+#include "bindings/core/v8/WindowProxy.h"
 #include "core/dom/Document.h"
 #include "core/dom/ExceptionCode.h"
 #include "core/dom/ExecutionContext.h"
 #include "core/dom/SecurityContext.h"
 #include "core/events/MessageEvent.h"
 #include "core/frame/External.h"
 #include "core/frame/Frame.h"
 #include "core/frame/FrameClient.h"
 #include "core/frame/FrameConsole.h"
 #include "core/frame/LocalDOMWindow.h"
@@ skipping 15 matching lines @@
 #include "platform/weborigin/Suborigin.h"
 #include <memory>
 
 namespace blink {
 
 DOMWindow::DOMWindow(Frame& frame) : m_frame(frame), m_windowIsClosing(false) {}
 
 DOMWindow::~DOMWindow() {
   // The frame must be disconnected before finalization.
   DCHECK(!m_frame);
+
+  // Because the wrapper object of a DOMWindow is the global proxy object which
+  // may live much longer than the DOMWindow, we need to dissociate all wrappers
+  // for this instance.
+  DOMWrapperWorld::dissociateWrappersInAllWorlds(this);
 }
 
-v8::Local<v8::Object> DOMWindow::wrap(v8::Isolate*,
+v8::Local<v8::Object> DOMWindow::wrap(v8::Isolate* isolate,
                                       v8::Local<v8::Object> creationContext) {
-  LOG(FATAL) << "DOMWindow must never be wrapped with wrap method.  The "
-                "wrappers must be created at WindowProxy::createContext() and "
-                "setupWindowPrototypeChain().";
-  return v8::Local<v8::Object>();
+  // Notice that we explicitly ignore |creationContext| because the DOMWindow
+  // has its own creation context.
+
+  Frame* frame = this->frame();
+  CHECK(frame);

[haraken, 2017/02/09 12:46:40]

Would you help me understand why frame is guaranteed to be non-null? In other
words, how is it guaranteed that the window is not yet detached?

[Yuki, 2017/02/10 07:47:21]

If WindowProxy::initialize() was already called, this DOMWindow object must be
already associated with a global proxy object as a wrapper object.  So, you
don't hit this line.

If you hit this line, the WindowProxy is not yet initialized due to the lazy
initialization.  I don't think there is a way to detach a window *BEFORE* its
initialization.  So the window must be attached.

+
+  v8::Local<v8::Object> globalProxy =
+      frame->windowProxy(DOMWrapperWorld::current(isolate))
+      ->globalIfNotDetached();
+  CHECK(!globalProxy.IsEmpty());
+
+  return globalProxy;
 }
 
 v8::Local<v8::Object> DOMWindow::associateWithWrapper(
     v8::Isolate*,
     const WrapperTypeInfo*,
     v8::Local<v8::Object> wrapper) {
-  LOG(FATAL) << "DOMWindow must never be wrapped with wrap method.  The "
-                "wrappers must be created at WindowProxy::createContext() and "
-                "setupWindowPrototypeChain().";
+  NOTREACHED();
   return v8::Local<v8::Object>();
 }
 
 const AtomicString& DOMWindow::interfaceName() const {
   return EventTargetNames::DOMWindow;
 }
 
 const DOMWindow* DOMWindow::toDOMWindow() const {
   return this;
 }
@@ skipping 374 matching lines @@
   page->focusController().focusDocumentView(frame(), true /* notifyEmbedder */);
 }
 
 DEFINE_TRACE(DOMWindow) {
   visitor->trace(m_frame);
   visitor->trace(m_location);
   EventTargetWithInlineData::trace(visitor);
 }
 
 }  // namespace blink