athena: Allow getting into split-view mode from overview-mode.

athena/wm/split_view_controller.h

 // Copyright 2014 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 ATHENA_WM_SPLIT_VIEW_CONTROLLER_H_
 #define ATHENA_WM_SPLIT_VIEW_CONTROLLER_H_
 
 #include "athena/wm/bezel_controller.h"
 #include "athena/wm/public/window_manager_observer.h"
 #include "athena/wm/window_overview_mode.h"
@@ skipping 15 matching lines @@
                             public WindowManagerObserver {
  public:
   SplitViewController(aura::Window* container,
                       WindowListProvider* window_list_provider,
                       WindowManager* window_manager);
 
   virtual ~SplitViewController();
 
   bool IsSplitViewModeActive() const;
 
+  // Activates split-view mode with |left| and |right| windows. If |left| and/or
+  // |right| is NULL, then the first window in the window-list (which is neither
+  // |left| nor |right|) is selected instead.
+  void ActivateSplitMode(aura::Window* left, aura::Window* right);
+
  private:
   enum State {
     // Split View mode is not active. |left_window_| and |right_window| are
     // NULL.
     INACTIVE,
     // Two windows |left_window_| and |right_window| are shown side by side and
     // there is a horizontal scroll in progress which is dragging the separator
     // between the two windows.
     SCROLLING,
     // Split View mode is active with |left_window_| and |right_window| showing
@@ skipping 52 matching lines @@
   int separator_position_;
 
   base::WeakPtrFactory<SplitViewController> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(SplitViewController);
 };
 
 }  // namespace athena
 
 #endif  // ATHENA_WM_SPLIT_VIEW_CONTROLLER_H_