phase based wheel scroll latching for mac

content/browser/renderer_host/render_widget_host_view_base.h

Index: content/browser/renderer_host/render_widget_host_view_base.h
diff --git a/content/browser/renderer_host/render_widget_host_view_base.h b/content/browser/renderer_host/render_widget_host_view_base.h
index c04ab0e05563ab87940bf9622ab74513ed4346eb..bcabd889464f2a220fb0b970bfd048d376c22d3f 100644
--- a/content/browser/renderer_host/render_widget_host_view_base.h
+++ b/content/browser/renderer_host/render_widget_host_view_base.h
@@ -68,6 +68,11 @@ struct DidOverscrollParams;
 }
 
 namespace content {
+
+// The duration after which a synthetic wheel with zero deltas and
+// phase = |kPhaseEnded| will be sent after the last wheel event.
+const int64_t kDefaultMouseWheelLatchingTransactionMs = 100;
+
 class BrowserAccessibilityDelegate;
 class BrowserAccessibilityManager;
 class RenderWidgetHostImpl;