Redesigns the text input focus handling.

ui/views/widget/desktop_aura/x11_desktop_handler.cc

Index: ui/views/widget/desktop_aura/x11_desktop_handler.cc
diff --git a/ui/views/widget/desktop_aura/x11_desktop_handler.cc b/ui/views/widget/desktop_aura/x11_desktop_handler.cc
index d98dfa644354d2590d7e42c20e4eb52eaa68fdd2..cfabbc85ebe0bddd3b2eb0f93d8f116c6480025f 100644
--- a/ui/views/widget/desktop_aura/x11_desktop_handler.cc
+++ b/ui/views/widget/desktop_aura/x11_desktop_handler.cc
@@ -186,12 +186,12 @@ void X11DesktopHandler::OnActiveWindowChanged(::Window xid) {
   if (old_host)
     old_host->HandleNativeWidgetActivationChanged(false);
 
+  current_window_ = xid;

[msw, 2014/03/11 00:58:50]

q: Why must the order of operations be changed here?

[Yuki, 2014/03/11 15:27:37]

I've added a comment.  The active widget must be changed before
HandleNativeWidgetActivationChanged(true) is called.

Handle...(false) behaves like Blur()
Handle...(true) behaves like Focus()
So between them, the active widget must be changed, so GetWidget()->IsActive()
returns the right value.

[msw, 2014/03/11 23:24:37]

Okay, this may have weird implications for code checking the active window
during this process; I guess any problems can be addressed if/when they arise.

[Yuki, 2014/03/12 09:13:15]

Will address any issues that would arise.

FocusManager checks if the widget is active or not during the call to
HandleNativeWidgetActivationChanged(), which indirectly calls
GetWidget()->GetFocusManager()->RestoreFocusedView().  At that time, the widget
must be active, otherwise the FocusManager won't set the focused view's
TextInputClient.

+
   DesktopWindowTreeHostX11* new_host =
       views::DesktopWindowTreeHostX11::GetHostForXID(xid);
   if (new_host)
     new_host->HandleNativeWidgetActivationChanged(true);
-
-  current_window_ = xid;
 }
 
 ::Window X11DesktopHandler::GetNextToActivateInStack(