Create the Tooltip widget in Aura as needed instead of just creating it in the timer.

ui/views/corewm/tooltip_controller.cc

Index: ui/views/corewm/tooltip_controller.cc
===================================================================
--- ui/views/corewm/tooltip_controller.cc	(revision 223170)
+++ ui/views/corewm/tooltip_controller.cc	(working copy)
@@ -87,6 +87,8 @@
 // Displays a widget with tooltip using a views::Label.
 class TooltipController::Tooltip : public views::WidgetObserver {
  public:
+  friend class TooltipController;
+
   Tooltip(TooltipController* controller)
       : controller_(controller),
         widget_(NULL) {
@@ -123,7 +125,6 @@
       width += 2 * kTooltipBorderWidth;
       height += 2 * kTooltipBorderWidth;
     }
-    GetWidgetForWindow(window);
     SetTooltipBounds(location, width, height);

[sky, 2013/09/16 22:46:51]

Won't this mean we potentially set the bounds only to recreate later on? And
similarly if you invoke GetWidgetForWindow later on and recreate the widget
won't the bounds be wrong?

[ananta, 2013/09/16 23:45:46]

As per our discussion, we now destroy the tooltip if the tooltip_window_ is
NULLed out.

   }
 
@@ -528,6 +529,8 @@
 TooltipController::Tooltip* TooltipController::GetTooltip() {
   if (!tooltip_.get())
     tooltip_.reset(new Tooltip(this));
+  if (tooltip_window_)
+    tooltip_->GetWidgetForWindow(tooltip_window_);

[sky, 2013/09/16 22:46:51]

I know we discussed invoking GetWidgetForWindow, but now that I see it this
isn't the right place. Or rather TooltipWindow should expose a better API for
this.

[ananta, 2013/09/16 23:45:46]

This is no longer needed.

   return tooltip_.get();
 }