Add support for constrained windows on os x, based on Avi's GTMWindowSheetController.

chrome/browser/cocoa/tab_window_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_TAB_WINDOW_CONTROLLER_H_
 #define CHROME_BROWSER_TAB_WINDOW_CONTROLLER_H_
 
 // A class acting as the Objective-C window controller for a window that has
 // tabs which can be dragged around. Tabs can be re-arranged within the same
 // window or dragged into other TabWindowController windows. This class doesn't
 // know anything about the actual tab implementation or model, as that is fairly
 // application-specific. It only provides an API to be overridden by subclasses
 // to fill in the details.
 //
 // This assumes that there will be a view in the nib, connected to
 // |tabContentArea_|, that indicates the content that it switched when switching
 // between tabs. It needs to be a regular NSView, not something like an NSBox
 // because the TabStripController makes certain assumptions about how it can
 // swap out subviews.
 
 #import <Cocoa/Cocoa.h>
 
+#include "base/scoped_nsobject.h"
+
 @class TabStripView;
 @class TabView;
 
 @interface TabWindowController : NSWindowController {
  @private
   IBOutlet NSView* tabContentArea_;
   IBOutlet TabStripView* tabStripView_;
   NSWindow* overlayWindow_;  // Used during dragging for window opacity tricks
   NSView* cachedContentView_;  // Used during dragging for identifying which
                                // view is the proper content area in the overlay
                                // (weak)
+  scoped_nsobject<NSMutableSet> lockedTabs_;
 }
 @property(readonly, nonatomic) TabStripView* tabStripView;
 @property(readonly, nonatomic) NSView* tabContentArea;
 
 // Used during tab dragging to turn on/off the overlay window when a tab
 // is torn off.
 - (void)showOverlay;
 - (void)removeOverlay;
 - (void)removeOverlayAfterDelay:(NSTimeInterval)delay;
 - (NSWindow*)overlayWindow;
@@ skipping 48 matching lines @@
 - (NSView *)selectedTabView;
 
 // The title of the selected tab.
 - (NSString*)selectedTabTitle;
 
 // Called to check if we are a normal window (e.g. not a pop-up) and
 // want normal behavior (e.g. a tab strip).  Return YES if so.  The
 // default implementation returns YES.
 - (BOOL)isNormalWindow;
 
+- (BOOL)isTabDraggable:(NSView*)tabView;
+- (void)setTab:(NSView*)tabView isDraggable:(BOOL)draggable;
 
 @end
 
 @interface TabWindowController(ProtectedMethods)
 // A list of all the views that need to move to the overlay window. Subclasses
 // can override this to add more things besides the tab strip. Be sure to
 // call the superclass' version if overridden.
 - (NSArray*)viewsToMoveToOverlay;
 
 // Tells the tab strip to forget about this tab in preparation for it being
 // put into a different tab strip, such as during a drop on another window.
 - (void)detachTabView:(NSView*)view;
 @end
 
 #endif  // CHROME_BROWSER_TAB_WINDOW_CONTROLLER_H_