Implement overscroll support for the virtual keyboard.

ash/shelf/shelf_layout_manager.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 "ash/shelf/shelf_layout_manager.h"
 
 #include <algorithm>
 #include <cmath>
 #include <cstring>
 #include <string>
@@ skipping 28 matching lines @@
 #include "ui/aura/client/cursor_client.h"
 #include "ui/aura/window_event_dispatcher.h"
 #include "ui/base/ui_base_switches.h"
 #include "ui/compositor/layer.h"
 #include "ui/compositor/layer_animation_observer.h"
 #include "ui/compositor/layer_animator.h"
 #include "ui/compositor/scoped_layer_animation_settings.h"
 #include "ui/events/event.h"
 #include "ui/events/event_handler.h"
 #include "ui/gfx/screen.h"
+#include "ui/keyboard/keyboard_util.h"
 #include "ui/views/widget/widget.h"
 #include "ui/wm/public/activation_client.h"
 
 namespace ash {
 namespace {
 
 // Delay before showing the shelf. This is after the mouse stops moving.
 const int kAutoHideDelayMS = 200;
 
 // To avoid hiding the shelf when the mouse transitions from a message bubble
@@ skipping 774 matching lines @@
       gfx::Insets(0, 0, GetWorkAreaSize(state, shelf_height), 0),
       gfx::Insets(0, GetWorkAreaSize(state, shelf_width), 0, 0),
       gfx::Insets(0, 0, 0, GetWorkAreaSize(state, shelf_width)),
       gfx::Insets(GetWorkAreaSize(state, shelf_height), 0, 0, 0));
 
   // TODO(varkha): The functionality of managing insets for display areas
   // should probably be pushed to a separate component. This would simplify or
   // remove entirely the dependency on keyboard and dock.
 
   // Also push in the work area inset for the keyboard if it is visible.
-  if (!keyboard_bounds_.IsEmpty()) {
+  if (!keyboard_bounds_.IsEmpty() && !keyboard::IsKeyboardOverscrollEnabled()) {
     gfx::Insets keyboard_insets(0, 0, keyboard_bounds_.height(), 0);
     target_bounds->work_area_insets += keyboard_insets;
   }
 
   // Also push in the work area inset for the dock if it is visible.
   if (!dock_bounds_.IsEmpty()) {
     gfx::Insets dock_insets(
         0, (dock_bounds_.x() > 0 ? 0 : dock_bounds_.width()),
         0, (dock_bounds_.x() > 0 ? dock_bounds_.width() : 0));
     target_bounds->work_area_insets += dock_insets;
@@ skipping 324 matching lines @@
 
 void ShelfLayoutManager::SessionStateChanged(
     SessionStateDelegate::SessionState state) {
   TargetBounds target_bounds;
   CalculateTargetBounds(state_, &target_bounds);
   UpdateBoundsAndOpacity(target_bounds, true, NULL);
   UpdateVisibilityState();
 }
 
 }  // namespace ash