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

ui/android/overscroll_glow.cc

Index: ui/android/overscroll_glow.cc
diff --git a/ui/android/overscroll_glow.cc b/ui/android/overscroll_glow.cc
index 7f3c43da3068c44a15e0fbb1e8a8f816619d8d16..b29b645d213867a758629cc21ed2b05d2b53907e 100644
--- a/ui/android/overscroll_glow.cc
+++ b/ui/android/overscroll_glow.cc
@@ -38,9 +38,7 @@ OverscrollGlow::OverscrollGlow(OverscrollGlowClient* client)
       edge_offsets_(),
       initialized_(false),
       allow_horizontal_overscroll_(true),
-      allow_vertical_overscroll_(true) {
-  DCHECK(client);
-}
+      allow_vertical_overscroll_(true) {}
 
 OverscrollGlow::~OverscrollGlow() {
   Detach();
@@ -194,6 +192,7 @@ bool OverscrollGlow::InitializeIfNecessary() {
     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();