Add ContextMenuSourceType to views::ContextMenuController::ShowContextMenuForView.

ui/views/controls/combobox/native_combobox_views.cc

Index: ui/views/controls/combobox/native_combobox_views.cc
diff --git a/ui/views/controls/combobox/native_combobox_views.cc b/ui/views/controls/combobox/native_combobox_views.cc
index 791598b7cbcdd22b5f40ead486c2b6861d6b3f0c..8ef1efa3102e649c8f7b184fc784f2228568abff 100644
--- a/ui/views/controls/combobox/native_combobox_views.cc
+++ b/ui/views/controls/combobox/native_combobox_views.cc
@@ -99,7 +99,7 @@ bool NativeComboboxViews::OnMousePressed(const ui::MouseEvent& mouse_event) {
   combobox_->RequestFocus();
   if (mouse_event.IsLeftMouseButton()) {
     UpdateFromModel();
-    ShowDropDownMenu();
+    ShowDropDownMenu(ui::MENU_SOURCE_MOUSE);
   }
 
   return true;
@@ -181,7 +181,7 @@ void NativeComboboxViews::OnBlur() {
 void NativeComboboxViews::OnGestureEvent(ui::GestureEvent* gesture) {
   if (gesture->type() == ui::ET_GESTURE_TAP) {
     UpdateFromModel();
-    ShowDropDownMenu();
+    ShowDropDownMenu(ui::MENU_SOURCE_TOUCH);
     gesture->StopPropagation();
     return;
   }
@@ -368,7 +368,7 @@ void NativeComboboxViews::PaintText(gfx::Canvas* canvas) {
   canvas->Restore();
 }
 
-void NativeComboboxViews::ShowDropDownMenu() {
+void NativeComboboxViews::ShowDropDownMenu(ui::MenuSourceType source_type) {
 
   if (!dropdown_list_menu_runner_.get())
     UpdateFromModel();
@@ -397,7 +397,8 @@ void NativeComboboxViews::ShowDropDownMenu() {
   dropdown_open_ = true;
   if (dropdown_list_menu_runner_->RunMenuAt(
           GetWidget(), NULL, bounds, MenuItemView::TOPLEFT,
-          MenuRunner::HAS_MNEMONICS) == MenuRunner::MENU_DELETED)
+          source_type, MenuRunner::HAS_MNEMONICS) ==
+      MenuRunner::MENU_DELETED)
     return;
   dropdown_open_ = false;