Desktop Aura: Allow tab drags out of window.

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

Index: chrome/browser/ui/views/tabs/tab_drag_controller.h
diff --git a/chrome/browser/ui/views/tabs/tab_drag_controller.h b/chrome/browser/ui/views/tabs/tab_drag_controller.h
index dd9f68dc2789890ea6ecff5df6290b9bb7c44b8b..a3c135496bd8335d23bd48fff86ad7fb846c8503 100644
--- a/chrome/browser/ui/views/tabs/tab_drag_controller.h
+++ b/chrome/browser/ui/views/tabs/tab_drag_controller.h
@@ -320,8 +320,11 @@ class TabDragController : public content::WebContentsDelegate,
   // runs a nested move loop.
   void DetachIntoNewBrowserAndRunMoveLoop(const gfx::Point& point_in_screen);
 
-  // Runs a nested message loop that handles moving the current Browser.
-  void RunMoveLoop();
+  // Runs a nested message loop that handles moving the current
+  // Browser. |drag_offset| is the offset from the window origin and is used in
+  // calculating the location of the window offset from the cursor while
+  // dragging.
+  void RunMoveLoop(const gfx::Point& drag_offset);
 
   // Determines the index to insert tabs at. |dragged_bounds| is the bounds of
   // the tabs being dragged, |start| the index of the tab to start looking from
@@ -428,6 +431,7 @@ class TabDragController : public content::WebContentsDelegate,
   // Creates and returns a new Browser to handle the drag.
   Browser* CreateBrowserForDrag(TabStrip* source,
                                 const gfx::Point& point_in_screen,
+                                gfx::Point* drag_offset,
                                 std::vector<gfx::Rect>* drag_bounds);
 
   // Returns the TabStripModel for the specified tabstrip.
@@ -437,6 +441,10 @@ class TabDragController : public content::WebContentsDelegate,
   // mouse or the location of the current touch point.
   gfx::Point GetCursorScreenPoint();
 
+  // Returns the offset from the top left corner of the window to
+  // |point_in_screen|.
+  gfx::Point GetWindowOffset(const gfx::Point& point_in_screen);
+
   // Returns true if moving the mouse only changes the visible tabs.
   bool move_only() const {
     return (move_behavior_ == MOVE_VISIBILE_TABS) != 0;