Implement dropping of tabs into an existing tab strip from another window.

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
@@ skipping 44 matching lines @@
 - (TabWindowController*)detachTabToNewWindow:(TabView*)tabView;
 
 // Make room in the tab strip for |tab| at the given x coordinate.
 - (void)insertPlaceholderForTab:(TabView*)tab
                           frame:(NSRect)frame
                   yStretchiness:(CGFloat)yStretchiness;
 
 // Removes the placeholder installed by |-insertPlaceholderForTab:atLocation:|.
 - (void)removePlaceholder;
 
+// Drop a given tab view at the location of the current placeholder. If there
+// is no placeholder, it will go at the end. |controller| is the window
+// controller of a tab being dropped from a different window. It will be nil
+// if the drag is within the window. The implementation will call
+// |-removePlaceholder| since the drag is now complete. This also calls
+// |-layoutTabs| internally so clients do not need to call it again. When
+// dragging tabs between windows, this should be called *before*
+// |-detachTabView| on the source window since it needs to still be in the
+// source window's tab model for this method to find the information it needs
+// to complete the drop.
+- (void)dropTabView:(NSView*)view
+     fromController:(TabWindowController*)controller;
+
+// 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;
+
 // Number of tabs in the tab strip. Useful, for example, to know if we're
 // dragging the only tab in the window.
 - (NSInteger)numberOfTabs;
 
 // Return the view of the selected tab.
 - (NSView *)selectedTabView;
 
-// Drop a given tab view at a new index.
-- (void)dropTabView:(NSView *)view atIndex:(NSUInteger)index;
-
 // The title of the selected tab.
 - (NSString*)selectedTabTitle;
 
 @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;
 @end
 
 #endif  // CHROME_BROWSER_TAB_WINDOW_CONTROLLER_H_