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

third_party/WebKit/Source/core/dom/Document.cpp

Index: third_party/WebKit/Source/core/dom/Document.cpp
diff --git a/third_party/WebKit/Source/core/dom/Document.cpp b/third_party/WebKit/Source/core/dom/Document.cpp
index 79e6b56486abab423bf7ca695de6a19b9bb20670..cc54cf2b04e920c28e1d939b9abebb8d81903b88 100644
--- a/third_party/WebKit/Source/core/dom/Document.cpp
+++ b/third_party/WebKit/Source/core/dom/Document.cpp
@@ -201,6 +201,7 @@
 #include "core/page/FrameTree.h"
 #include "core/page/Page.h"
 #include "core/page/PointerLockController.h"
+#include "core/page/scrolling/OverscrollController.h"
 #include "core/page/scrolling/RootScrollerController.h"
 #include "core/page/scrolling/ScrollStateCallback.h"
 #include "core/page/scrolling/ScrollingCoordinator.h"
@@ -1971,6 +1972,19 @@ void Document::InheritHtmlAndBodyElementStyles(StyleRecalcChange change) {
   }
 
   ScrollSnapType snap_type = overflow_style->GetScrollSnapType();
+  EScrollBoundaryBehavior scroll_boundary_behavior_x =
+      overflow_style->ScrollBoundaryBehaviorX();
+  EScrollBoundaryBehavior scroll_boundary_behavior_y =
+      overflow_style->ScrollBoundaryBehaviorY();
+  using ScrollBoundaryBehaviorType =
+      WebScrollBoundaryBehavior::ScrollBoundaryBehaviorType;
+  if (RuntimeEnabledFeatures::CSSScrollBoundaryBehaviorEnabled()) {
+    GetPage()->GetOverscrollController().SetScrollBoundaryBehavior(

[majidvp, 2017/07/21 15:24:12]

If I understand this correctly, the current logic allows any document in
the page to control the overscroll navigation behavior of the page. Meaning that
if I have this css property on an iframe then it will prevent the navigation.
This is incorrect.

We should only allow the top level document to control this behavior. Which I
think means limiting this to when |Document::IsInMainFrame()| is true.

Also, this suggests to me that we are missing a few tests. For example there is
no test covering this. I suspect you can add tests to WebFrameTest to ensure we
receive the correct values according to the css property and whether this is the
main frame or not.

[sunyunjia, 2017/07/25 20:20:55]

Done.

+        WebScrollBoundaryBehavior(
+            static_cast<ScrollBoundaryBehaviorType>(scroll_boundary_behavior_x),
+            static_cast<ScrollBoundaryBehaviorType>(
+                scroll_boundary_behavior_y)));
+  }
 
   RefPtr<ComputedStyle> viewport_style = GetLayoutViewItem().MutableStyle();
   if (viewport_style->GetWritingMode() != root_writing_mode ||
@@ -1983,7 +1997,9 @@ void Document::InheritHtmlAndBodyElementStyles(StyleRecalcChange change) {
       viewport_style->OverflowX() != overflow_x ||
       viewport_style->OverflowY() != overflow_y ||
       viewport_style->ColumnGap() != column_gap ||
-      viewport_style->GetScrollSnapType() != snap_type) {
+      viewport_style->GetScrollSnapType() != snap_type ||
+      viewport_style->ScrollBoundaryBehaviorX() != scroll_boundary_behavior_x ||
+      viewport_style->ScrollBoundaryBehaviorY() != scroll_boundary_behavior_y) {
     RefPtr<ComputedStyle> new_style = ComputedStyle::Clone(*viewport_style);
     new_style->SetWritingMode(root_writing_mode);
     new_style->SetDirection(root_direction);
@@ -1995,6 +2011,8 @@ void Document::InheritHtmlAndBodyElementStyles(StyleRecalcChange change) {
     new_style->SetOverflowY(overflow_y);
     new_style->SetColumnGap(column_gap);
     new_style->SetScrollSnapType(snap_type);
+    new_style->SetScrollBoundaryBehaviorX(scroll_boundary_behavior_x);
+    new_style->SetScrollBoundaryBehaviorY(scroll_boundary_behavior_y);
     GetLayoutViewItem().SetStyle(new_style);
     SetupFontBuilder(*new_style);
   }