MacViews: Support continuous scrolling and horizontal scrolling

ui/views/controls/scroll_view.cc

Index: ui/views/controls/scroll_view.cc
diff --git a/ui/views/controls/scroll_view.cc b/ui/views/controls/scroll_view.cc
index ec83c884ff54220b7550995092b4e8757d4d2d68..d12c73b0732f75d9f434970fc16038c2f7e15908 100644
--- a/ui/views/controls/scroll_view.cc
+++ b/ui/views/controls/scroll_view.cc
@@ -354,12 +354,12 @@ bool ScrollView::OnKeyPressed(const ui::KeyEvent& event) {
 
 bool ScrollView::OnMouseWheel(const ui::MouseWheelEvent& e) {
   bool processed = false;
-  // Give vertical scrollbar priority
+
   if (vert_sb_->visible())
     processed = vert_sb_->OnMouseWheel(e);
 
-  if (!processed && horiz_sb_->visible())
-    processed = horiz_sb_->OnMouseWheel(e);
+  if (horiz_sb_->visible())
+    processed = horiz_sb_->OnMouseWheel(e) || processed;

[sky, 2014/09/02 18:25:54]

Why this change? Doesn't this mean we always send to both vert/horizontal even
if vertical processed it?

[Andre, 2014/09/02 18:30:52]

Yes, BaseScrollBar::OnMouseWheel always returns true so the horizontal never
gets a chance.
Also, some events may have both x and y offsets.

 
   return processed;
 }