MacViews: Implement Tab Dragging

chrome/browser/ui/views/tabs/tab_drag_controller.cc

 // Copyright (c) 2012 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/ui/views/tabs/tab_drag_controller.h"
 
 #include <math.h>
 #include <set>
 
 #include "base/auto_reset.h"
@@ skipping 364 matching lines @@
                           point_in_screen.x() -
                           mouse_offset_.x(), 0);
         widget->SetVisibilityChangedAnimationsEnabled(false);
         widget->Restore();
         widget->SetBounds(new_bounds);
         AdjustBrowserAndTabBoundsForDrag(last_tabstrip_width,
                                          point_in_screen,
                                          &drag_bounds);
         widget->SetVisibilityChangedAnimationsEnabled(true);
       }
-      RunMoveLoop(GetWindowOffset(point_in_screen));
+      RunMoveLoop(GetWindowOffset(start_point_in_screen_));
       return;
     }
   }
 
   ContinueDragging(point_in_screen);
 }
 
 void TabDragController::EndDrag(EndDragReason reason) {
   TRACE_EVENT0("views", "TabDragController::EndDrag");
 
@@ skipping 1411 matching lines @@
   // window which was used for dragging is not hidden once all of its tabs are
   // attached to another browser window in DragBrowserToNewTabStrip().
   // TODO(pkotwicz): Fix this properly (crbug.com/358482)
   for (auto* browser : *BrowserList::GetInstance()) {
     if (browser->tab_strip_model()->empty())
       exclude.insert(browser->window()->GetNativeWindow());
   }
 #endif
   return GetLocalProcessWindowAtPoint(screen_point, exclude);
 }