Ensure WindowProxy reinitialization on navigations if needed.

third_party/WebKit/Source/bindings/core/v8/LocalWindowProxy.cpp

 /*
  * Copyright (C) 2008, 2009, 2011 Google 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 84 matching lines @@
   v8::Local<v8::Context> context = m_scriptState->context();
   if (m_globalProxy.isEmpty()) {
     m_globalProxy.set(isolate(), context->Global());
     CHECK(!m_globalProxy.isEmpty());
   }
 
   setupWindowPrototypeChain();
 
   SecurityOrigin* origin = 0;
   if (m_world->isMainWorld()) {
-    // ActivityLogger for main world is updated within updateDocument().
-    updateDocument();
+    // ActivityLogger for main world is updated within updateDocumentInternal().
+    updateDocumentInternal();
     origin = frame()->document()->getSecurityOrigin();
     // FIXME: Can this be removed when CSP moves to browser?
     ContentSecurityPolicy* csp = frame()->document()->contentSecurityPolicy();
     context->AllowCodeGenerationFromStrings(
         csp->allowEval(0, SecurityViolationReportingPolicy::SuppressReporting));
     context->SetErrorMessageForCodeGenerationFromStrings(
         v8String(isolate(), csp->evalDisabledErrorMessage()));
   } else {
     updateActivityLogger();
     origin = m_world->isolatedWorldSecurityOrigin();
@@ skipping 119 matching lines @@
   // as the security token.
   context->SetSecurityToken(v8AtomicString(isolate(), token));
 }
 
 void LocalWindowProxy::updateDocument() {
   DCHECK(m_world->isMainWorld());
   // For an uninitialized main window proxy, there's nothing we need
   // to update. The update is done when the window proxy gets initialized later.
   if (m_lifecycle == Lifecycle::ContextUninitialized)
     return;
-  // TODO(yukishiino): Is it okay to not update document when the context
-  // is detached? It's not trivial to fix this because udpateDocumentProperty
-  // requires a not-yet-detached context to instantiate a document wrapper.
-  if (m_lifecycle == Lifecycle::ContextDetached)
+
+  // If this WindowProxy was previously initialized, reinitialize it now to
+  // preserve JS object identity. Otherwise, extant references to the
+  // WindowProxy will be broken.
+  if (m_lifecycle == Lifecycle::ContextDetached) {
+    initialize();
+    DCHECK_EQ(Lifecycle::ContextInitialized, m_lifecycle);
+    // Initialization internally updates the document properties, so just
+    // return afterwards.
     return;
+  }
 
+  updateDocumentInternal();
+}
+
+void LocalWindowProxy::updateDocumentInternal() {
   updateActivityLogger();
   updateDocumentProperty();
   updateSecurityOrigin(frame()->document()->getSecurityOrigin());
 }
 
 static v8::Local<v8::Value> getNamedProperty(
     HTMLDocument* htmlDocument,
     const AtomicString& key,
     v8::Local<v8::Object> creationContext,
     v8::Isolate* isolate) {
@@ skipping 93 matching lines @@
 
   setSecurityToken(origin);
 }
 
 LocalWindowProxy::LocalWindowProxy(v8::Isolate* isolate,
                                    LocalFrame& frame,
                                    RefPtr<DOMWrapperWorld> world)
     : WindowProxy(isolate, frame, std::move(world)) {}
 
 }  // namespace blink