cros: Use runtime stylus detection for ash palette.

ash/magnifier/partial_magnification_controller.cc

Index: ash/magnifier/partial_magnification_controller.cc
diff --git a/ash/magnifier/partial_magnification_controller.cc b/ash/magnifier/partial_magnification_controller.cc
index b4fc5c022fa22ba89eddc2c6587d629a0516d287..8cd64f62ce1015162d50d746e494f245f6520c06 100644
--- a/ash/magnifier/partial_magnification_controller.cc
+++ b/ash/magnifier/partial_magnification_controller.cc
@@ -283,7 +283,7 @@ void PartialMagnificationController::OnLocatedEvent(
 
   // If the stylus is pressed on the palette icon or widget, do not activate.
   if (event->type() == ui::ET_TOUCH_PRESSED &&
-      !PaletteContainsPointInScreen(screen_point)) {
+      !palette_utils::PaletteContainsPointInScreen(screen_point)) {
     SetActive(true);
   }
 
@@ -311,7 +311,7 @@ void PartialMagnificationController::OnLocatedEvent(
   host_widget_->SetBounds(GetBounds(point));
 
   // If the stylus is over the palette icon or widget, do not consume the event.
-  if (!PaletteContainsPointInScreen(screen_point))
+  if (!palette_utils::PaletteContainsPointInScreen(screen_point))
     event->StopPropagation();
 }