Revert of Clean up WindowEventDispatcher some more.

mojo/examples/aura_demo/window_tree_host_mojo.cc

Index: mojo/examples/aura_demo/window_tree_host_mojo.cc
diff --git a/mojo/examples/aura_demo/window_tree_host_mojo.cc b/mojo/examples/aura_demo/window_tree_host_mojo.cc
index 815cce66fed668e5277c762b666b23b5bd408ff3..266d9231811914746f06ad00e14835573a67239c 100644
--- a/mojo/examples/aura_demo/window_tree_host_mojo.cc
+++ b/mojo/examples/aura_demo/window_tree_host_mojo.cc
@@ -10,7 +10,7 @@
 #include "mojo/services/native_viewport/geometry_conversions.h"
 #include "ui/aura/env.h"
 #include "ui/aura/window.h"
-#include "ui/aura/window_event_dispatcher.h"
+#include "ui/aura/window_tree_host_delegate.h"
 #include "ui/compositor/compositor.h"
 #include "ui/events/event.h"
 #include "ui/events/event_constants.h"
@@ -148,7 +148,7 @@
 // WindowTreeHostMojo, ui::EventSource implementation:
 
 ui::EventProcessor* WindowTreeHostMojo::GetEventProcessor() {
-  return dispatcher();
+  return delegate_->GetEventProcessor();
 }
 
 ////////////////////////////////////////////////////////////////////////////////
@@ -162,7 +162,8 @@
 void WindowTreeHostMojo::OnBoundsChanged(const Rect& bounds) {
   bounds_ = gfx::Rect(bounds.position().x(), bounds.position().y(),
                       bounds.size().width(), bounds.size().height());
-  window()->SetBounds(gfx::Rect(bounds_.size()));
+  if (delegate_)
+    window()->SetBounds(gfx::Rect(bounds_.size()));
   OnHostResized(bounds_.size());
 }