Touch gestures for System Tray/ IME/ Stylus/ Notifications

ash/system/ime_menu/ime_menu_tray.cc

Index: ash/system/ime_menu/ime_menu_tray.cc
diff --git a/ash/system/ime_menu/ime_menu_tray.cc b/ash/system/ime_menu/ime_menu_tray.cc
index df15493b0e9bdbf761bcf795c5098bda8f458828..bd5e591782dc5f290247eabbed9f2dd2dd174702 100644
--- a/ash/system/ime_menu/ime_menu_tray.cc
+++ b/ash/system/ime_menu/ime_menu_tray.cc
@@ -470,6 +470,33 @@ bool ImeMenuTray::PerformAction(const ui::Event& event) {
   return true;
 }
 
+bool ImeMenuTray::HasBubble() {
+  return bubble_.get() != NULL;

[msw, 2017/07/12 05:04:50]

nit: this should be moot, but use nullptr instead of NULL.

[minch1, 2017/07/13 19:10:34]

Done.

+}
+
+void ImeMenuTray::CloseBubble() {
+  HideImeMenuBubble();
+}
+
+void ImeMenuTray::ShowBubble() {
+  ShowImeMenuBubble();
+}
+
+views::TrayBubbleView* ImeMenuTray::GetBubbleView() {
+  if (HasBubble())

[msw, 2017/07/12 05:04:50]

nit: return bubble_ ? bubble_->bubble_view() : nullptr;
(ditto elsewhere for the other impls)

[minch1, 2017/07/13 19:10:34]

Done.

+    return bubble_->bubble_view();
+  return nullptr;
+}
+
+void ImeMenuTray::OnGestureEvent(ui::GestureEvent* event) {
+  if (drag_controller()->ProcessGestureEvent(*event, this,
+                                             false /* is_on_bubble */)) {
+    event->SetHandled();

[msw, 2017/07/12 05:04:50]

Please make DragController::ProcessGestureEvent take an event pointer and call
SetHandled() on it directly (as needed), so each caller doesn't have to do this,
and then you can simplify the callers like this:
  if (!drag_controller()->ProcessGestureEvent(event, this, false)
    TrayBackgroundView::OnGestureEvent(event);

[minch1, 2017/07/13 19:10:34]

Done.

+  } else {
+    TrayBackgroundView::OnGestureEvent(event);
+  }
+}
+
 void ImeMenuTray::OnIMERefresh() {
   UpdateTrayLabel();
   if (bubble_ && ime_list_view_) {
@@ -519,6 +546,10 @@ void ImeMenuTray::HideBubble(const views::TrayBubbleView* bubble_view) {
   HideBubbleWithView(bubble_view);
 }
 
+bool ImeMenuTray::ProcessGestureEventForBubble(ui::GestureEvent* event) {
+  return drag_controller()->ProcessGestureEvent(*event, this,
+                                                true /* is_on_bubble */);
+}
 void ImeMenuTray::OnKeyboardBoundsChanging(const gfx::Rect& new_bounds) {}
 
 void ImeMenuTray::OnKeyboardClosed() {