Add support for pinning platform apps

ash/launcher/launcher_model.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/launcher/launcher_model.h"
 
 #include <algorithm>
 
 #include "ash/launcher/launcher_model_observer.h"
 #include "ui/aura/window.h"
@@ skipping 72 matching lines @@
   // TODO: this needs to enforce valid ranges.
   LauncherItem item(items_[index]);
   items_.erase(items_.begin() + index);
   items_.insert(items_.begin() + target_index, item);
   FOR_EACH_OBSERVER(LauncherModelObserver, observers_,
                     LauncherItemMoved(index, target_index));
 }
 
 void LauncherModel::Set(int index, const LauncherItem& item) {
   DCHECK(index >= 0 && index < item_count());
+  int new_index = item.type == items_[index].type ?
+      index : ValidateInsertionIndex(item.type, index);
+
   LauncherItem old_item(items_[index]);
   items_[index] = item;
   items_[index].id = old_item.id;
-  items_[index].type = old_item.type;
   FOR_EACH_OBSERVER(LauncherModelObserver, observers_,
                     LauncherItemChanged(index, old_item));
+
+  // If the type changes confirm that the item is still in the right order.
+  if (new_index != index)
+      Move(index, new_index);

[sky, 2012/06/13 23:43:27]

nit: spacing is off.

 }
 
 int LauncherModel::ItemIndexByID(LauncherID id) {
   LauncherItems::const_iterator i = ItemByID(id);
   return i == items_.end() ? -1 : static_cast<int>(i - items_.begin());
 }
 
 LauncherItems::const_iterator LauncherModel::ItemByID(int id) const {
   for (LauncherItems::const_iterator i = items_.begin();
        i != items_.end(); ++i) {
@@ skipping 22 matching lines @@
                                     CompareByWeight) - items_.begin(),
                    static_cast<LauncherItems::difference_type>(index));
   index = std::min(std::upper_bound(items_.begin(), items_.end(), weight_dummy,
                                     CompareByWeight) - items_.begin(),
                    static_cast<LauncherItems::difference_type>(index));
 
   return index;
 }
 
 }  // namespace ash