[ash-md] Adds support for gesture to move selection in overview mode

ash/common/wm/overview/window_selector.cc

 // Copyright 2013 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 "ash/common/wm/overview/window_selector.h"
 
 #include <algorithm>
 #include <functional>
 #include <set>
 #include <utility>
@@ skipping 389 matching lines @@
     selected_grid_index_--;
     // If the grid which became empty was the one with the selected window, we
     // need to select a window on the newly selected grid.
     if (selected_grid_index_ == index - 1)
       Move(LEFT, true);
   }
   if (grid_list_.empty())
     CancelSelection();
 }
 
+void WindowSelector::IncrementSelection(int increment) {
+  const Direction direction =
+      increment > 0 ? WindowSelector::RIGHT : WindowSelector::LEFT;
+  for (int step = 0; step < abs(increment); ++step)
+    Move(direction, true);
+}
+
+bool WindowSelector::AcceptSelection() {
+  if (!grid_list_[selected_grid_index_]->is_selecting())
+    return false;
+  SelectWindow(grid_list_[selected_grid_index_]->SelectedWindow());
+  return true;
+}
+
 void WindowSelector::SelectWindow(WindowSelectorItem* item) {
   WmWindow* window = item->GetWindow();
   std::vector<WmWindow*> window_list =
       WmShell::Get()->mru_window_tracker()->BuildMruWindowList();
   if (!window_list.empty()) {
     // Record UMA_WINDOW_OVERVIEW_ACTIVE_WINDOW_CHANGED if the user is selecting
     // a window other than the window that was active prior to entering overview
     // mode (i.e., the window at the front of the MRU list).
     if (window_list[0] != window) {
       WmShell::Get()->RecordUserMetricsAction(
@@ skipping 246 matching lines @@
   for (size_t i = 0; i <= grid_list_.size() &&
                      grid_list_[selected_grid_index_]->Move(direction, animate);
        i++) {
     selected_grid_index_ =
         (selected_grid_index_ + display_direction + grid_list_.size()) %
         grid_list_.size();
   }
 }
 
 }  // namespace ash