Set ui::KeyEvent::key_ (DOM Level 3 key) under X11.

ui/events/event.cc

Index: ui/events/event.cc
diff --git a/ui/events/event.cc b/ui/events/event.cc
index fdf17f994039d6a57cd5da943f6e5fff981d3086..f38ed8e4f362531daffb5a5c8f31f92368ff45e6 100644
--- a/ui/events/event.cc
+++ b/ui/events/event.cc
@@ -805,8 +805,7 @@ void KeyEvent::ApplyLayout() const {
   // returns 'a' for VKEY_A even if the key is actually bound to 'à' in X11.
   // GetCharacterFromXEvent returns 'à' in that case.
   if (!IsControlDown() && native_event()) {
-    character_ = GetCharacterFromXEvent(native_event());
-    // TODO(kpschoedel): set key_ field for X11.
+    GetMeaningFromXEvent(native_event(), &key_, &character_);
     return;
   }
 #elif defined(USE_OZONE)