[Mac] Refactor the logic of tab dragging out of TabView and into a new helper.

chrome/browser/ui/cocoa/tabs/tab_view.h

 // Copyright (c) 2011 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_UI_COCOA_TABS_TAB_VIEW_H_
 #define CHROME_BROWSER_UI_COCOA_TABS_TAB_VIEW_H_
 #pragma once
 
 #import <Cocoa/Cocoa.h>
 #include <ApplicationServices/ApplicationServices.h>
 
-#include <map>
-
 #include "base/memory/scoped_nsobject.h"
 #import "chrome/browser/ui/cocoa/background_gradient_view.h"
 #import "chrome/browser/ui/cocoa/hover_close_button.h"
 
 namespace tabs {
 
 // Nomenclature:
 // Tabs _glow_ under two different circumstances, when they are _hovered_ (by
 // the mouse) and when they are _alerted_ (to show that the tab's title has
 // changed).
@@ skipping 35 matching lines @@
   CGFloat hoverAlpha_;  // How strong the hover glow is.
   NSTimeInterval hoverHoldEndTime_;  // When the hover glow will begin dimming.
 
   CGFloat alertAlpha_;  // How strong the alert glow is.
   NSTimeInterval alertHoldEndTime_;  // When the hover glow will begin dimming.
 
   NSTimeInterval lastGlowUpdate_;  // Time either glow was last updated.
 
   NSPoint hoverPoint_;  // Current location of hover in view coords.
 
-  // All following variables are valid for the duration of a drag.
-  // These are released on mouseUp:
-  BOOL moveWindowOnDrag_;  // Set if the only tab of a window is dragged.
-  BOOL tabWasDragged_;  // Has the tab been dragged?
-  BOOL draggingWithinTabStrip_;  // Did drag stay in the current tab strip?
-  BOOL chromeIsVisible_;
+  // The location of the current mouseDown event in window coordinates.
+  NSPoint mouseDownPoint_;
 
-  NSTimeInterval tearTime_;  // Time since tear happened
-  NSPoint tearOrigin_;  // Origin of the tear rect
-  NSPoint dragOrigin_;  // Origin point of the drag
-  // TODO(alcor): these references may need to be strong to avoid crashes
-  // due to JS closing windows
-  TabWindowController* sourceController_;  // weak. controller starting the drag
-  NSWindow* sourceWindow_;  // weak. The window starting the drag
-  NSRect sourceWindowFrame_;
-  NSRect sourceTabFrame_;
-
-  TabWindowController* draggedController_;  // weak. Controller being dragged.
-  NSWindow* dragWindow_;  // weak. The window being dragged
-  NSWindow* dragOverlay_;  // weak. The overlay being dragged
-  // Cache workspace IDs per-drag because computing them on 10.5 with
-  // CGWindowListCreateDescriptionFromArray is expensive.
-  // resetDragControllers clears this cache.
-  //
-  // TODO(davidben): When 10.5 becomes unsupported, remove this.
-  std::map<CGWindowID, int> workspaceIDCache_;
-
-  TabWindowController* targetController_;  // weak. Controller being targeted
   NSCellStateValue state_;
 }
 
 @property(assign, nonatomic) NSCellStateValue state;
 @property(assign, nonatomic) CGFloat hoverAlpha;
 @property(assign, nonatomic) CGFloat alertAlpha;
 
 // Determines if the tab is in the process of animating closed. It may still
 // be visible on-screen, but should not respond to/initiate any events. Upon
 // setting to NO, clears the target/action of the close button to prevent
@@ skipping 15 matching lines @@
 
 // The TabController |controller_| is not the only owner of this view. If the
 // controller is released before this view, then we could be hanging onto a
 // garbage pointer. To prevent this, the TabController uses this interface to
 // clear the |controller_| pointer when it is dying.
 @interface TabView (TabControllerInterface)
 - (void)setController:(TabController*)controller;
 @end
 
 #endif  // CHROME_BROWSER_UI_COCOA_TABS_TAB_VIEW_H_