events: Update key-event handlers to not return EventResult.

ash/wm/overlay_event_filter.cc

Index: ash/wm/overlay_event_filter.cc
diff --git a/ash/wm/overlay_event_filter.cc b/ash/wm/overlay_event_filter.cc
index 1a333b7bb330a982ec9d74c4a10e80ff0c00695b..2319d2fca27b6ddc07e3d0d36ed7db70e7080da5 100644
--- a/ash/wm/overlay_event_filter.cc
+++ b/ash/wm/overlay_event_filter.cc
@@ -21,9 +21,9 @@ OverlayEventFilter::~OverlayEventFilter() {
   delegate_ = NULL;
 }
 
-ui::EventResult OverlayEventFilter::OnKeyEvent(ui::KeyEvent* event) {
+void OverlayEventFilter::OnKeyEvent(ui::KeyEvent* event) {
   if (!delegate_)
-    return ui::ER_UNHANDLED;
+    return;
 
   // Do not consume a translated key event which is generated by an IME (e.g.,
   // ui::VKEY_PROCESSKEY) since the key event is generated in response to a key
@@ -31,7 +31,7 @@ ui::EventResult OverlayEventFilter::OnKeyEvent(ui::KeyEvent* event) {
   // confuse key event handling JavaScript code in a page.
   if (event->type() == ui::ET_TRANSLATED_KEY_PRESS ||
       event->type() == ui::ET_TRANSLATED_KEY_RELEASE) {
-    return ui::ER_UNHANDLED;
+    return;
   }
 
   if (delegate_ && delegate_->IsCancelingKeyEvent(event))
@@ -46,7 +46,7 @@ ui::EventResult OverlayEventFilter::OnKeyEvent(ui::KeyEvent* event) {
 
   // Always handled: other windows shouldn't receive input while we're
   // displaying an overlay.
-  return ui::ER_CONSUMED;
+  event->StopPropagation();
 }
 
 void OverlayEventFilter::OnLoginStateChanged(