Remove an isGlobalInitialized() check from WindowProxy::updateDocument()

Context states transit from Uninitialized to Initialized, and then to Detached.

- isGlobalInitialized() returns true when the context state is Initialized or Detached.
- isContextInitialized() returns true when the context state is Initialized.

Thus !isContextInitialized() is stronger than !isGlobalInitialized().
Hence we can remove if(!isGlobalInitialized()) from WindowProxy::updateDocument().

BUG=677253

Review-Url: https://codereview.chromium.org/2603953002
Cr-Commit-Position: refs/heads/master@{#440842}

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

@@ -460,10 +460,9 @@ void WindowProxy::setSecurityToken(SecurityOrigin* origin) {
 
 void WindowProxy::updateDocument() {
   DCHECK(m_world->isMainWorld());
-  if (!isGlobalInitialized())
-    return;
   if (!isContextInitialized())
     return;
+
   updateActivityLogger();
   updateDocumentProperty();
   updateSecurityOrigin(m_frame->securityContext()->getSecurityOrigin());