Extract shell methods from ApplicationImpl into a base class, and pass this to Initialize() instead.

mash/shelf/shelf_view.cc

 // Copyright 2015 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 "mash/shelf/shelf_view.h"
 
 #include <algorithm>
 
 #include "base/auto_reset.h"
 #include "mash/shelf/shelf_button.h"
@@ skipping 212 matching lines @@
     view_->layer()->SetOpacity(1.0f);
   }
 
  private:
   ShelfView* shelf_view_;
   views::View* view_;
 
   DISALLOW_COPY_AND_ASSIGN(StartFadeAnimationDelegate);
 };
 
-ShelfView::ShelfView(mojo::ApplicationImpl* app)
-    : app_(app),
-      model_(app),
+ShelfView::ShelfView(mojo::Shell* shell)
+    : shell_(shell),
+      model_(shell),
       alignment_(SHELF_ALIGNMENT_BOTTOM),
       first_visible_index_(0),
       last_visible_index_(-1),
       /* TODO(msw): Restore functionality:
       overflow_button_(nullptr),
       owner_overflow_bubble_(nullptr),*/
       tooltip_(this),
       drag_pointer_(NONE),
       drag_view_(nullptr),
       start_drag_index_(-1),
@@ skipping 1658 matching lines @@
       break;
     case SHELF_ALIGNMENT_TOP:
       distance = coordinate.y() - bounds.bottom();
       break;
   }
   return distance > 0 ? distance : 0;
 }
 
 }  // namespace shelf
 }  // namespace mash