Mac: Only show one per-tab sheet at a time per tab.

chrome/browser/cocoa/tab_strip_controller.h

 // 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.
 
 #ifndef CHROME_BROWSER_COCOA_TAB_STRIP_CONTROLLER_H_
 #define CHROME_BROWSER_COCOA_TAB_STRIP_CONTROLLER_H_
 
 #import <Cocoa/Cocoa.h>
 
+#include <deque>
+#include <map>
+
 #include "base/scoped_nsobject.h"
 #include "base/scoped_ptr.h"
 #import "chrome/browser/cocoa/tab_controller_target.h"
 #import "third_party/GTM/AppKit/GTMWindowSheetController.h"
 
 @class TabView;
 @class TabStripView;
 
 class Browser;
 class ConstrainedWindowMac;
@@ skipping 69 matching lines @@
 
   // Array of subviews which are permanent (and which should never be removed),
   // such as the new-tab button, but *not* the tabs themselves.
   scoped_nsobject<NSMutableArray> permanentSubviews_;
 
   // The default favicon, so we can use one copy for all buttons.
   scoped_nsobject<NSImage> defaultFavIcon_;
 
   // Manages per-tab sheets.
   scoped_nsobject<GTMWindowSheetController> sheetController_;
+
+  // GTMWindowSheetController supports only one per-tab sheet at a time.
+  // Thus, keep a queue of sheets for every tab. The first element in the queue
+  // is the currently visible sheet, and when this sheet is closed, the next
+  // sheet in the queue will be shown.
+  std::map<NSView*, std::deque<ConstrainedWindowMac*> > constrainedWindows_;
 }
 
 // Initialize the controller with a view and browser that contains
 // everything else we'll need. |switchView| is the view whose contents get
 // "switched" every time the user switches tabs. The children of this view
 // will be released, so if you want them to stay around, make sure
 // you have retained them.
 - (id)initWithView:(TabStripView*)view
         switchView:(NSView*)switchView
            browser:(Browser*)browser;
@@ skipping 53 matching lines @@
 // For example, this returns NO if there are any pending tab close animtations.
 - (BOOL)tabDraggingAllowed;
 
 // Default height for tabs.
 + (CGFloat)defaultTabHeight;
 
 // Returns the (lazily created) window sheet controller of this window. Used
 // for the per-tab sheets.
 - (GTMWindowSheetController*)sheetController;
 
-- (void)attachConstrainedWindow:(ConstrainedWindowMac*)window;
+// See comments in browser_window_controller.h for documentation about these
+// functions.
+- (BOOL)attachConstrainedWindow:(ConstrainedWindowMac*)window;
 - (void)removeConstrainedWindow:(ConstrainedWindowMac*)window;
 
 @end
 
 // Notification sent when the number of tabs changes. The object will be this
 // controller.
 extern NSString* const kTabStripNumberOfTabsChanged;
 
 #endif  // CHROME_BROWSER_COCOA_TAB_STRIP_CONTROLLER_H_