aura: Fix build after r108132 and r108048.

TBR=ben@chromium.org
BUG=none
TEST=none

Review URL: http://codereview.chromium.org/8423015

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@108142 0039d316-1c4b-4281-b951-d872f2087c98

chrome/browser/ui/views/notifications/balloon_view_host.cc

@@ -69,7 +69,7 @@ void BalloonViewHost::InitRenderWidgetHostView() {
 #if defined(USE_AURA)
   RenderWidgetHostViewAura* view_aura =
       static_cast<RenderWidgetHostViewAura*>(render_widget_host_view_);
-  view_aura->Init();
+  view_aura->InitAsChild();
   view_aura->Show();
   native_host_->Attach(view_aura->GetNativeView());
 #elif defined(OS_WIN)