mash: Introduce ShowWebDialogWithContainer for webui dialogs

chrome/browser/ui/webui/options/chromeos/date_time_options_handler.cc

Index: chrome/browser/ui/webui/options/chromeos/date_time_options_handler.cc
diff --git a/chrome/browser/ui/webui/options/chromeos/date_time_options_handler.cc b/chrome/browser/ui/webui/options/chromeos/date_time_options_handler.cc
index 5e8f81a64ecb30c51b1dcad979042b5c145011dc..f976012b32b1b0b12dbd98620b76bd91beef2a09 100644
--- a/chrome/browser/ui/webui/options/chromeos/date_time_options_handler.cc
+++ b/chrome/browser/ui/webui/options/chromeos/date_time_options_handler.cc
@@ -68,7 +68,7 @@ void DateTimeOptionsHandler::SystemClockCanSetTimeChanged(bool can_set_time) {
 void DateTimeOptionsHandler::HandleShowSetTime(const base::ListValue* args) {
   // Make sure the clock status hasn't changed since the button was clicked.
   if (can_set_time_) {
-    SetTimeDialog::ShowDialog(
+    SetTimeDialog::ShowDialogInParent(
         web_ui()->GetWebContents()->GetTopLevelNativeWindow());
   }
 }