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

content/browser/android/overscroll_controller_android.cc

 // 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.
 
 #include "content/browser/android/overscroll_controller_android.h"
 
 #include "base/android/build_info.h"
 #include "base/command_line.h"
 #include "base/memory/ptr_util.h"
 #include "cc/layers/layer.h"
@@ skipping 110 matching lines @@
   // Suppress refresh detection if the glow effect is still prominent.
   if (glow_effect_ && glow_effect_->IsActive()) {
     if (glow_effect_->GetVisibleAlpha() > MinGlowAlphaToDisableRefresh())
       return false;
   }
 
   bool handled = false;
   switch (event.GetType()) {
     case blink::WebInputEvent::kGestureScrollBegin:
       refresh_effect_->OnScrollBegin();
+      consumed_ = false;
       break;
 
     case blink::WebInputEvent::kGestureScrollUpdate: {
       gfx::Vector2dF scroll_delta(event.data.scroll_update.delta_x,
                                   event.data.scroll_update.delta_y);
       scroll_delta.Scale(dpi_scale_);
       handled = refresh_effect_->WillHandleScrollUpdate(scroll_delta);
+      LOG(ERROR) << handled;

[majidvp, 2017/05/18 15:26:10]

remove.

[sunyunjia, 2017/05/19 20:14:23]

Done.

     } break;
 
     case blink::WebInputEvent::kGestureScrollEnd:
       refresh_effect_->OnScrollEnd(gfx::Vector2dF());
       break;
 
     case blink::WebInputEvent::kGestureFlingStart: {
       if (refresh_effect_->IsActive()) {
         gfx::Vector2dF scroll_velocity(event.data.fling_start.velocity_x,
                                        event.data.fling_start.velocity_y);
@@ skipping 34 matching lines @@
   // sent from the renderer compositor.
   if (event.GetType() == blink::WebInputEvent::kGestureScrollEnd ||
       event.GetType() == blink::WebInputEvent::kGestureFlingStart) {
     OnOverscrolled(DidOverscrollParams());
   }
 
   if (event.GetType() == blink::WebInputEvent::kGestureScrollUpdate &&
       refresh_effect_) {
     // The effect should only be allowed if both the causal touch events go
     // unconsumed and the generated scroll events go unconsumed.
-    bool consumed =
-        ack_result == INPUT_EVENT_ACK_STATE_CONSUMED ||
-        event.data.scroll_update.previous_update_in_sequence_prevented;
-    refresh_effect_->OnScrollUpdateAck(consumed);
+    consumed_ = ack_result == INPUT_EVENT_ACK_STATE_CONSUMED ||
+                event.data.scroll_update.previous_update_in_sequence_prevented;
   }
 }
 
 void OverscrollControllerAndroid::OnOverscrolled(
-    const DidOverscrollParams& params) {
+    const DidOverscrollParams& overscroll_params) {
   if (!enabled_)
     return;
 
+  DidOverscrollParams params = overscroll_params;
+
+  if (refresh_effect_) {
+    if (params.scroll_boundary_behavior.y ==
+        cc::ScrollBoundaryBehavior::ScrollBoundaryBehaviorType::
+            kScrollBoundaryBehaviorTypeAuto)
+      refresh_effect_->OnScrollUpdateAck(consumed_);
+    else
+      refresh_effect_->OnScrollUpdateAck(true);

[majidvp, 2017/05/18 15:26:10]

This method is no longer invoked on ScrollUpdateAck also its
input is no longer just the consumed state but also involves scroll boundary
behavior. So I think it makes sense
to make changes to the signature e.g.,

OverscrollRefresh::OnOverscrolled(bool can_navigate)

where:

bool can_navigate = !consumed_ && scroll_boundary_behavior.y ==             
kScrollBoundaryBehaviorTypeAuto 

[sunyunjia, 2017/05/19 20:14:23]

Done.

+  }
+
   if (refresh_effect_ && (refresh_effect_->IsActive() ||
                           refresh_effect_->IsAwaitingScrollUpdateAck())) {

[majidvp, 2017/05/18 15:26:10]

nit: the first condition is the same of the above so you can 
merge the two.

[sunyunjia, 2017/05/19 20:14:23]

Done.

     // An active (or potentially active) refresh effect should always pre-empt
     // the passive glow effect.
     return;
   }
 
+  if (params.scroll_boundary_behavior.y ==
+      cc::ScrollBoundaryBehavior::ScrollBoundaryBehaviorType::
+          kScrollBoundaryBehaviorTypeNone)
+    params.ClearY();
+
+  if (params.scroll_boundary_behavior.x ==
+      cc::ScrollBoundaryBehavior::ScrollBoundaryBehaviorType::
+          kScrollBoundaryBehaviorTypeNone)
+    params.ClearX();

[majidvp, 2017/05/18 15:26:10]

I believe this is for glow. So please update the CL description to
mention glow as well.

Also it will be good to explain in CL that we are now making the
decision to p2r also on DidOverscrollParams as opposed to immediately
after ScrollUpdateAck.

[sunyunjia, 2017/05/19 20:14:23]

Done.

+
   if (glow_effect_ &&
       glow_effect_->OnOverscrolled(
           base::TimeTicks::Now(),
           gfx::ScaleVector2d(params.accumulated_overscroll, dpi_scale_),
           gfx::ScaleVector2d(params.latest_overscroll_delta, dpi_scale_),
           gfx::ScaleVector2d(params.current_fling_velocity, dpi_scale_),
           gfx::ScaleVector2d(
               params.causal_event_viewport_point.OffsetFromOrigin(),
               dpi_scale_))) {
     SetNeedsAnimate();
@@ skipping 53 matching lines @@
 std::unique_ptr<EdgeEffectBase>
 OverscrollControllerAndroid::CreateEdgeEffect() {
   return CreateGlowEdgeEffect(&compositor_->GetResourceManager(), dpi_scale_);
 }
 
 void OverscrollControllerAndroid::SetNeedsAnimate() {
   compositor_->SetNeedsAnimate();
 }
 
 }  // namespace content