[Android] Disable pull-to-refresh with overflow:hidden

content/browser/android/overscroll_refresh.h

 // Copyright 2014 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 CONTENT_BROWSER_ANDROID_OVERSCROLL_REFRESH_H_
 #define CONTENT_BROWSER_ANDROID_OVERSCROLL_REFRESH_H_
 
 #include "base/memory/scoped_ptr.h"
 #include "base/time/time.h"
 #include "content/common/content_export.h"
@@ skipping 19 matching lines @@
   // should cause a refresh of some kind, e.g., page reload.
   virtual void TriggerRefresh() = 0;
 
   // Whether the triggered refresh has yet to complete. The effect will continue
   // animating until the refresh completes (or it reaches a reasonable timeout).
   virtual bool IsStillRefreshing() const = 0;
 };
 
 // Simple pull-to-refresh styled effect. Listens to scroll events, conditionally
 // activating when:
-//   1) The scroll begins when the page has no vertical scroll offset.
+//   1) The scroll begins when the page's root layer 1) has no vertical scroll
+//      offset and 2) lacks the overflow-y:hidden property.
 //   2) The page doesn't consume the initial scroll events.
 //   3) The initial scroll direction is upward.
 // The actual page reload action is triggered only when the effect is active
 // and beyond a particular threshold when released.
 class CONTENT_EXPORT OverscrollRefresh {
  public:
   // Both |resource_manager| and |client| must not be null.
   // |target_drag_offset_pixels| is the threshold beyond which the effect
   // will trigger a refresh action when released. When |mirror| is true,
   // the effect and its rotation will be mirrored about the y axis.
@@ skipping 18 matching lines @@
   void ReleaseWithoutActivation();
 
   // Returns true if the effect still needs animation ticks, with effect layers
   // attached to |parent| if necessary.
   // Note: The effect will detach itself when no further animation is required.
   bool Animate(base::TimeTicks current_time, cc::Layer* parent_layer);
 
   // Update the effect according to the most recent display parameters,
   // Note: All dimensions are in device pixels.
   void UpdateDisplay(const gfx::SizeF& viewport_size,
-                     const gfx::Vector2dF& content_scroll_offset);
+                     const gfx::Vector2dF& content_scroll_offset,
+                     bool root_overflow_y_hidden);
 
   // Reset the effect to its inactive state, immediately detaching and
   // disabling any active effects.
   void Reset();
 
   // Returns true if the refresh effect is either being manipulated or animated.
   bool IsActive() const;
 
   // Returns true if the effect is waiting for an unconsumed scroll to start.
   bool IsAwaitingScrollUpdateAck() const;
 
  private:
   void Release(bool allow_activation);
 
   OverscrollRefreshClient* const client_;
 
   gfx::SizeF viewport_size_;
   bool scrolled_to_top_;
+  bool overflow_y_hidden_;
 
   enum ScrollConsumptionState {
     DISABLED,
     AWAITING_SCROLL_UPDATE_ACK,
     ENABLED,
   } scroll_consumption_state_;
 
   class Effect;
   scoped_ptr<Effect> effect_;
 
   DISALLOW_COPY_AND_ASSIGN(OverscrollRefresh);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_ANDROID_OVERSCROLL_REFRESH_H_