Revert 170795

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

Index: chrome/browser/ui/cocoa/constrained_window/constrained_window_mac2.mm
===================================================================
--- chrome/browser/ui/cocoa/constrained_window/constrained_window_mac2.mm	(revision 170901)
+++ chrome/browser/ui/cocoa/constrained_window/constrained_window_mac2.mm	(working copy)
@@ -10,8 +10,6 @@
 #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"
 
@@ -21,17 +19,12 @@
     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() {
@@ -39,12 +32,12 @@
 
 void ConstrainedWindowMac2::ShowConstrainedWindow() {
   NSWindow* parent_window = GetParentWindow();
-  NSView* parent_view = GetSheetParentViewForWebContents(web_contents_);
-  if (!parent_window || !parent_view) {
-    pending_show_ = true;
+  if (!parent_window)
     return;
-  }
 
+  NSView* parent_view = GetSheetParentViewForWebContents(web_contents_);
+  DCHECK(parent_view);
+
   ConstrainedWindowSheetController* controller =
       [ConstrainedWindowSheetController
           controllerForParentWindow:parent_window];
@@ -52,10 +45,6 @@
 }
 
 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 =
@@ -81,21 +70,6 @@
   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.