App List: Refactor ContentsSwitcherView so it doesn't hard-code pages.

ui/app_list/views/app_list_main_view.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 "ui/app_list/views/app_list_main_view.h"
 
 #include <algorithm>
 
 #include "base/bind.h"
 #include "base/callback.h"
@@ skipping 91 matching lines @@
   // Switch the apps grid view to the specified page.
   app_list::PaginationModel* pagination_model = GetAppsPaginationModel();
   if (pagination_model->is_valid_page(initial_apps_page))
     pagination_model->SelectPage(initial_apps_page, false);
 
   // Starts icon loading early.
   PreloadIcons(parent);
 }
 
 void AppListMainView::AddContentsView() {
-  contents_view_ = new ContentsView(this, model_, delegate_);
+  if (app_list::switches::IsExperimentalAppListEnabled())
+    contents_switcher_view_ = new ContentsSwitcherView();
+  contents_view_ =
+      new ContentsView(this, contents_switcher_view_, model_, delegate_);

[calamity, 2014/06/18 05:22:29]

I think ContentsSwitcherView should take ContentsView as a constructor param and
not vice versa. It makes sense for a ContentsView to exist without a
ContentsSwitcherView but not the opposite.

You could move the page creation into a ContentsView::InitNamedPages() and have
set_contents_switcher_view().

[Matt Giuca, 2014/06/18 06:47:02]

Done. Good suggestion.

   DCHECK_EQ(1, child_count());
   AddChildView(contents_view_);
-  if (app_list::switches::IsExperimentalAppListEnabled()) {
-    contents_switcher_view_ = new ContentsSwitcherView(contents_view_);
+  if (contents_switcher_view_) {
+    contents_switcher_view_->Init(contents_view_);
     AddChildView(contents_switcher_view_);
   }
 
   search_box_view_->set_contents_view(contents_view_);
 
   contents_view_->SetPaintToLayer(true);
   contents_view_->SetFillsBoundsOpaquely(false);
   contents_view_->layer()->SetMasksToBounds(true);
 }
 
@@ skipping 163 matching lines @@
   // Resubmit the query via a posted task so that all observers for the
   // uninstall notification are notified.
   base::MessageLoop::current()->PostTask(
       FROM_HERE,
       base::Bind(&AppListMainView::QueryChanged,
                  weak_ptr_factory_.GetWeakPtr(),
                  search_box_view_));
 }
 
 }  // namespace app_list