Reusing Ok/Cancel buttons for intent picker

ui/views/controls/scroll_view.h

 // 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.
 
 #ifndef UI_VIEWS_CONTROLS_SCROLL_VIEW_H_
 #define UI_VIEWS_CONTROLS_SCROLL_VIEW_H_
 
 #include <string>
 
 #include "base/compiler_specific.h"
@@ skipping 88 matching lines @@
   void OnScrollEvent(ui::ScrollEvent* event) override;
   void OnGestureEvent(ui::GestureEvent* event) override;
   const char* GetClassName() const override;
 
   // ScrollBarController overrides:
   void ScrollToPosition(ScrollBar* source, int position) override;
   int GetScrollIncrement(ScrollBar* source,
                          bool is_page,
                          bool is_positive) override;
 
+  // Activate a Layer() for the |contents_viewport_| if the passed parameter is
+  // true or any of the children in the ScrollView contains a layer.
+  void ActivateLayer(bool force_layer_creation);
+
  private:
   friend class test::ScrollViewTestApi;
 
   class Viewport;
 
   // Used internally by SetHeader() and SetContents() to reset the view.  Sets
   // |member| to |new_view|. If |new_view| is non-null it is added to |parent|.
   void SetHeaderOrContents(View* parent, View* new_view, View** member);
 
   // Scrolls the minimum amount necessary to make the specified rectangle
@@ skipping 17 matching lines @@
   void UpdateScrollBarPositions();
 
   // Helpers to get and set the current scroll offset (either from the ui::Layer
   // or from the |contents_| origin offset).
   gfx::ScrollOffset CurrentOffset() const;
   void ScrollToOffset(const gfx::ScrollOffset& offset);
 
   // Whether the ScrollView scrolls using ui::Layer APIs.
   bool ScrollsWithLayers() const;
 
+  // Whether any of the children in the |child|-rooted subtree has a layer.
+  bool ChildrenLayerCheck(View* child) const;
+
   // Callback entrypoint when hosted Layers are scrolled by the Compositor.
   void OnLayerScrolled();
 
   // Horizontally scrolls the header (if any) to match the contents.
   void ScrollHeader();
 
   // The current contents and its viewport. |contents_| is contained in
   // |contents_viewport_|.
   View* contents_;
   View* contents_viewport_;
@@ skipping 94 matching lines @@
  private:
   int top_margin_;
   int row_height_;
 
   DISALLOW_COPY_AND_ASSIGN(FixedRowHeightScrollHelper);
 };
 
 }  // namespace views
 
 #endif  // UI_VIEWS_CONTROLS_SCROLL_VIEW_H_