Use scroll-boundary-behavior to control overscroll-refresh/glow on android.

ui/android/overscroll_glow.cc

 // Copyright (c) 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.
 
 #include "ui/android/overscroll_glow.h"
 
 #include <stddef.h>
 
 #include "cc/layers/layer.h"
 #include "ui/android/edge_effect_base.h"
@@ skipping 20 matching lines @@
   return vector;
 }
 
 }  // namespace
 
 OverscrollGlow::OverscrollGlow(OverscrollGlowClient* client)
     : client_(client),
       edge_offsets_(),
       initialized_(false),
       allow_horizontal_overscroll_(true),
-      allow_vertical_overscroll_(true) {
-  DCHECK(client);

[boliu, 2017/08/23 19:17:02]

ditto fix test rather than relax production checks

[sunyunjia, 2017/08/23 23:47:05]

Done.

-}
+      allow_vertical_overscroll_(true) {}
 
 OverscrollGlow::~OverscrollGlow() {
   Detach();
 }
 
 void OverscrollGlow::Reset() {
   if (!initialized_)
     return;
   Detach();
   for (size_t i = 0; i < EDGE_COUNT; ++i)
@@ skipping 133 matching lines @@
 void OverscrollGlow::Detach() {
   if (root_layer_.get())
     root_layer_->RemoveFromParent();
 }
 
 bool OverscrollGlow::InitializeIfNecessary() {
   if (initialized_)
     return true;
 
   DCHECK(!root_layer_.get());
+  DCHECK(client_);
   root_layer_ = cc::Layer::Create();
   for (size_t i = 0; i < EDGE_COUNT; ++i) {
     edge_effects_[i] = client_->CreateEdgeEffect();
     DCHECK(edge_effects_[i]);
   }
 
   initialized_ = true;
   return true;
 }
 
@@ skipping 65 matching lines @@
   for (size_t i = 0; i < EDGE_COUNT; ++i)
     edge_effects_[i]->Release(current_time);
 }
 
 EdgeEffectBase* OverscrollGlow::GetOppositeEdge(int edge_index) {
   DCHECK(initialized_);
   return edge_effects_[(edge_index + 2) % EDGE_COUNT].get();
 }
 
 }  // namespace ui