Revert 170795

chrome/browser/ui/cocoa/constrained_window/constrained_window_mac2.mm

 // Copyright (c) 2012 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 "chrome/browser/ui/cocoa/constrained_window/constrained_window_mac2.h"
 
 #include "base/logging.h"
 #include "chrome/browser/ui/browser_finder.h"
 #include "chrome/browser/ui/browser_window.h"
 #include "chrome/browser/ui/cocoa/constrained_window/constrained_window_sheet_controller.h"
 #include "chrome/browser/ui/cocoa/tabs/tab_strip_controller.h"
 #include "chrome/browser/ui/constrained_window_tab_helper.h"
-#include "content/public/browser/notification_source.h"
-#include "content/public/browser/notification_types.h"
 #include "content/public/browser/web_contents.h"
 #include "content/public/browser/web_contents_view.h"
 
 ConstrainedWindowMac2::ConstrainedWindowMac2(
     ConstrainedWindowMacDelegate2* delegate,
     content::WebContents* web_contents,
     NSWindow* window)
     : delegate_(delegate),
       web_contents_(web_contents),
-      window_([window retain]),
-      pending_show_(false) {
+      window_([window retain]) {
   DCHECK(web_contents);
   DCHECK(window_.get());
   ConstrainedWindowTabHelper* constrained_window_tab_helper =
       ConstrainedWindowTabHelper::FromWebContents(web_contents);
   constrained_window_tab_helper->AddConstrainedDialog(this);
-
-  registrar_.Add(this,
-                 content::NOTIFICATION_WEB_CONTENTS_VISIBILITY_CHANGED,
-                 content::Source<content::WebContents>(web_contents));
 }
 
 ConstrainedWindowMac2::~ConstrainedWindowMac2() {
 }
 
 void ConstrainedWindowMac2::ShowConstrainedWindow() {
   NSWindow* parent_window = GetParentWindow();
+  if (!parent_window)
+    return;
+
   NSView* parent_view = GetSheetParentViewForWebContents(web_contents_);
-  if (!parent_window || !parent_view) {
-    pending_show_ = true;
-    return;
-  }
+  DCHECK(parent_view);
 
   ConstrainedWindowSheetController* controller =
       [ConstrainedWindowSheetController
           controllerForParentWindow:parent_window];
   [controller showSheet:window_ forParentView:parent_view];
 }
 
 void ConstrainedWindowMac2::CloseConstrainedWindow() {
-  // This function may be called even if the constrained window was never shown.
-  // Unset |pending_show_| to prevent the window from being reshown.
-  pending_show_ = false;
-
   [[ConstrainedWindowSheetController controllerForSheet:window_]
       closeSheet:window_];
   ConstrainedWindowTabHelper* constrained_window_tab_helper =
       ConstrainedWindowTabHelper::FromWebContents(web_contents_);
   constrained_window_tab_helper->WillClose(this);
   if (delegate_)
     delegate_->OnConstrainedWindowClosed(this);
 }
 
 void ConstrainedWindowMac2::PulseConstrainedWindow() {
   [[ConstrainedWindowSheetController controllerForSheet:window_]
       pulseSheet:window_];
 }
 
 gfx::NativeWindow ConstrainedWindowMac2::GetNativeWindow() {
   return window_;
 }
 
 bool ConstrainedWindowMac2::CanShowConstrainedWindow() {
   Browser* browser = chrome::FindBrowserWithWebContents(web_contents_);
   if (!browser)
     return true;
   return !browser->window()->IsInstantTabShowing();
 }
 
-void ConstrainedWindowMac2::Observe(
-    int type,
-    const content::NotificationSource& source,
-    const content::NotificationDetails& details) {
-  if (type != content::NOTIFICATION_WEB_CONTENTS_VISIBILITY_CHANGED) {
-    NOTREACHED();
-    return;
-  }
-
-  if (pending_show_) {
-    pending_show_ = false;
-    ShowConstrainedWindow();
-  }
-}
-
 NSWindow* ConstrainedWindowMac2::GetParentWindow() const {
   // Tab contents in a tabbed browser may not be inside a window. For this
   // reason use a browser window if possible.
   Browser* browser = chrome::FindBrowserWithWebContents(web_contents_);
   if (browser)
     return browser->window()->GetNativeWindow();
 
   return web_contents_->GetView()->GetTopLevelNativeWindow();
 }