Enforce that only one constrained window is displayed at once per tab.

chrome/browser/gtk/constrained_window_gtk.cc

 // Copyright (c) 2009 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/gtk/constrained_window_gtk.h"
 
 #include "chrome/browser/tab_contents/tab_contents.h"
 #include "chrome/browser/tab_contents/tab_contents_view_gtk.h"
 #include "chrome/common/gtk_util.h"
 
 ConstrainedWindowGtk::ConstrainedWindowGtk(
     TabContents* owner, ConstrainedWindowGtkDelegate* delegate)
     : owner_(owner),
-      delegate_(delegate) {
+      delegate_(delegate),
+      visible_(false) {
   DCHECK(owner);
   DCHECK(delegate);
   GtkWidget* dialog = delegate->GetWidgetRoot();
 
   // Unlike other users of CreateBorderBin, we need a dedicated frame around
   // our "window".
   GtkWidget* ebox = gtk_event_box_new();
   GtkWidget* frame = gtk_frame_new(NULL);
   gtk_frame_set_shadow_type(GTK_FRAME(frame), GTK_SHADOW_OUT);
   GtkWidget* alignment = gtk_alignment_new(0.0, 0.0, 1.0, 1.0);
   gtk_alignment_set_padding(GTK_ALIGNMENT(alignment),
       gtk_util::kContentAreaBorder, gtk_util::kContentAreaBorder,
       gtk_util::kContentAreaBorder, gtk_util::kContentAreaBorder);
   gtk_container_add(GTK_CONTAINER(alignment), dialog);
   gtk_container_add(GTK_CONTAINER(frame), alignment);
   gtk_container_add(GTK_CONTAINER(ebox), frame);
   border_.Own(ebox);
-
-  gtk_widget_show_all(border_.get());
-
-  // We collaborate with TabContentsViewGtk and stick ourselves in the
-  // TabContentsViewGtk's floating container.
-  ContainingView()->AttachConstrainedWindow(this);
 }
 
 ConstrainedWindowGtk::~ConstrainedWindowGtk() {
   border_.Destroy();
 }
 
+void ConstrainedWindowGtk::ShowConstrainedWindow() {
+  gtk_widget_show_all(border_.get());
+
+  // We collaborate with TabContentsViewGtk and stick ourselves in the
+  // TabContentsViewGtk's floating container.
+  ContainingView()->AttachConstrainedWindow(this);
+
+  visible_ = true;
+}
+
 void ConstrainedWindowGtk::CloseConstrainedWindow() {
-  ContainingView()->RemoveConstrainedWindow(this);
+  if (visible_)
+    ContainingView()->RemoveConstrainedWindow(this);
   delegate_->DeleteDelegate();
   owner_->WillClose(this);
 
   delete this;
 }
 
 TabContentsViewGtk* ConstrainedWindowGtk::ContainingView() {
   return static_cast<TabContentsViewGtk*>(owner_->view());
 }
 
 // static
 ConstrainedWindow* ConstrainedWindow::CreateConstrainedDialog(
     TabContents* parent,
     ConstrainedWindowGtkDelegate* delegate) {
   return new ConstrainedWindowGtk(parent, delegate);
 }