Set ImeListView's scrollable range when updating

ash/common/system/chromeos/ime_menu/ime_menu_tray.cc

Index: ash/common/system/chromeos/ime_menu/ime_menu_tray.cc
diff --git a/ash/common/system/chromeos/ime_menu/ime_menu_tray.cc b/ash/common/system/chromeos/ime_menu/ime_menu_tray.cc
index cf8bf8c3a79e8adb3a62d84b5be2359a438d569d..1981e0a9625417c24a68b32ab4500e45659f3e68 100644
--- a/ash/common/system/chromeos/ime_menu/ime_menu_tray.cc
+++ b/ash/common/system/chromeos/ime_menu/ime_menu_tray.cc
@@ -473,13 +473,8 @@ bool ImeMenuTray::PerformAction(const ui::Event& event) {
 void ImeMenuTray::OnIMERefresh() {
   UpdateTrayLabel();
   if (bubble_ && ime_list_view_) {
-    SystemTrayDelegate* delegate = WmShell::Get()->system_tray_delegate();
-    IMEInfoList list;
-    delegate->GetAvailableIMEList(&list);
-    IMEPropertyInfoList property_list;
-    delegate->GetCurrentIMEProperties(&property_list);
-    ime_list_view_->Update(list, property_list, false,
-                           ImeListView::SHOW_SINGLE_IME);
+    HideImeMenuBubble();
+    ShowImeMenuBubble();

[tdanderson, 2016/11/30 23:04:15]

I'm not sure that hiding and re-showing the bubble is really the ideal fix for
this bug; wouldn't the menu look like it's "flickering" to the user (when it
hides and re-shows quickly)?

I tried the keyboard shortcut in the IME detailed view in the system menu, and
it seems to work fine. Can you look into how the detailed view handles changes
via keyboard shortcut and do something similar for the opt-in menu?

[Azure Wei, 2016/12/01 00:33:30]

The IME detailed view and opt-in menu shares the same updating logic. And opt-in
menu used to work fine when switching with shortcuts. I suspects this could be
regression related to scroll content of TrayDetailsView. But I didn't find out
where goes wrong.

Anyway, this isn't a good solution to fix. Let me hold this CL and try other
ways.

   }
 }