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

cc/trees/layer_tree_host_impl.cc

 // Copyright 2011 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 "cc/trees/layer_tree_host_impl.h"
 
 #include <algorithm>
 #include <limits>
 
 #include "base/basictypes.h"
@@ skipping 1428 matching lines @@
   if (top_controls_manager_) {
     metadata.location_bar_offset =
         gfx::Vector2dF(0.f, top_controls_manager_->ControlsTopOffset());
     metadata.location_bar_content_translation =
         gfx::Vector2dF(0.f, top_controls_manager_->ContentTopOffset());
   }
 
   active_tree_->GetViewportSelection(&metadata.selection_start,
                                      &metadata.selection_end);
 
+  LayerImpl* root_layer_for_overflow = OuterViewportScrollLayer()
+                                           ? OuterViewportScrollLayer()
+                                           : InnerViewportScrollLayer();
+  if (root_layer_for_overflow) {
+    metadata.root_overflow_x_hidden =
+        !root_layer_for_overflow->user_scrollable_horizontal();
+    metadata.root_overflow_y_hidden =
+        !root_layer_for_overflow->user_scrollable_vertical();
+  }
+
   if (!InnerViewportScrollLayer())
     return metadata;
 
   // TODO(miletus) : Change the metadata to hold ScrollOffset.
   metadata.root_scroll_offset = gfx::ScrollOffsetToVector2dF(
       active_tree_->TotalScrollOffset());
 
   return metadata;
 }
 
@@ skipping 1198 matching lines @@
           layer_impl, pending_delta, active_tree_->current_page_scale_factor());
     }
 
     const float kEpsilon = 0.1f;
     if (layer_impl == InnerViewportScrollLayer()) {
       unused_root_delta.Subtract(applied_delta);
       if (std::abs(unused_root_delta.x()) < kEpsilon)
         unused_root_delta.set_x(0.0f);
       if (std::abs(unused_root_delta.y()) < kEpsilon)
         unused_root_delta.set_y(0.0f);
+
+      // If there is unconsumed scroll after application to the viewport, and
+      // the (outer) viewport layer is explicitly marked unscrollable, suppress
+      // any overscroll, preventing bubbling to UI layers.
+      const LayerImpl* layer_for_user_scrollable_testing =

[jdduke (slow), 2015/02/11 22:22:56]

Oops, I'll go ahead and revert this change, it's not necessary for the patch.

+          OuterViewportScrollLayer() ? OuterViewportScrollLayer() : layer_impl;
+      if (unused_root_delta.x() &&
+          !layer_for_user_scrollable_testing->user_scrollable_horizontal()) {
+        unused_root_delta.set_x(0);
+      }
+      if (unused_root_delta.y() &&
+          !layer_for_user_scrollable_testing->user_scrollable_vertical()) {
+        unused_root_delta.set_y(0);
+      }
+
       // Disable overscroll on axes which is impossible to scroll.
       if (settings_.report_overscroll_only_for_scrollable_axes) {
-        if (std::abs(active_tree_->TotalMaxScrollOffset().x()) <= kEpsilon ||
-            !layer_impl->user_scrollable_horizontal())
+        if (std::abs(active_tree_->TotalMaxScrollOffset().x()) <= kEpsilon)
           unused_root_delta.set_x(0.0f);
-        if (std::abs(active_tree_->TotalMaxScrollOffset().y()) <= kEpsilon ||
-            !layer_impl->user_scrollable_vertical())
+        if (std::abs(active_tree_->TotalMaxScrollOffset().y()) <= kEpsilon)
           unused_root_delta.set_y(0.0f);
       }
     }
 
     // Scrolls should bubble perfectly between the outer and inner viewports.
     bool allow_unrestricted_bubbling_for_current_layer =
         layer_impl == OuterViewportScrollLayer();
     bool allow_bubbling_for_current_layer =
         allow_unrestricted_bubbling_for_current_layer || should_bubble_scrolls_;
 
@@ skipping 801 matching lines @@
     (*it)->OnSetNeedsRedrawOnImpl();
 }
 
 void LayerTreeHostImpl::NotifySwapPromiseMonitorsOfForwardingToMainThread() {
   std::set<SwapPromiseMonitor*>::iterator it = swap_promise_monitor_.begin();
   for (; it != swap_promise_monitor_.end(); it++)
     (*it)->OnForwardScrollUpdateToMainThreadOnImpl();
 }
 
 }  // namespace cc