Expose FS show/hide thresholds to Command Line

cc/top_controls_manager.h

 // 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.
 
 #ifndef CC_TOP_CONTROLS_MANAGER_H_
 #define CC_TOP_CONTROLS_MANAGER_H_
 
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/weak_ptr.h"
 #include "cc/layer_impl.h"
@@ skipping 12 matching lines @@
 
 // Manages the position of the top controls.
 class CC_EXPORT TopControlsManager {
  public:
   enum AnimationDirection {
     NO_ANIMATION,
     SHOWING_CONTROLS,
     HIDING_CONTROLS
   };
 
-  static scoped_ptr<TopControlsManager> Create(TopControlsManagerClient* client,
-                                               float top_controls_height);
+  static scoped_ptr<TopControlsManager> Create(
+      TopControlsManagerClient* client,
+      float top_controls_height,
+      float top_controls_show_threshold,
+      float top_controls_hide_threshold);
   virtual ~TopControlsManager();
 
   float controls_top_offset() { return controls_top_offset_; }
   float content_top_offset() { return content_top_offset_; }
   KeyframedFloatAnimationCurve* animation() {
     return top_controls_animation_.get();
   }
   AnimationDirection animation_direction() { return animation_direction_; }
 
   void ScrollBegin();
   gfx::Vector2dF ScrollBy(const gfx::Vector2dF pending_delta);
   void ScrollEnd();
 
   void Animate(base::TimeTicks monotonic_time);
 
  protected:
   TopControlsManager(TopControlsManagerClient* client,
-                     float top_controls_height);
+                     float top_controls_height,
+                     float top_controls_show_threshold,
+                     float top_controls_hide_threshold);
 
  private:
   gfx::Vector2dF ScrollInternal(const gfx::Vector2dF pending_delta);
   void ResetAnimations();
   float RootScrollLayerTotalScrollY();
   void SetupAnimation(AnimationDirection direction);
   void StartAnimationIfNecessary();
   bool IsAnimationCompleteAtTime(base::TimeTicks time);
 
   TopControlsManagerClient* client_;  // The client manages the lifecycle of
                                       // this.
 
   scoped_ptr<KeyframedFloatAnimationCurve> top_controls_animation_;
   AnimationDirection animation_direction_;
   bool in_scroll_gesture_;
   float controls_top_offset_;
   float content_top_offset_;
   float top_controls_height_;
   float previous_root_scroll_offset_;
   float scroll_start_offset_;
+  float current_scroll_delta_;
+
+  // The height of the visible top control such that it must be shown when
+  // the user stops the scroll.
+  float top_controls_show_height_;
+
+  // The height of the visible top control such that it must be hidden when
+  // the user stops the scroll.
+  float top_controls_hide_height_;
 
   DISALLOW_COPY_AND_ASSIGN(TopControlsManager);
 };
 
 }  // namespace cc
 
 #endif  // CC_TOP_CONTROLS_MANAGER_H_