Make Mandoline shut down cleanly.

components/native_viewport/platform_viewport_x11.cc

Index: components/native_viewport/platform_viewport_x11.cc
diff --git a/components/native_viewport/platform_viewport_x11.cc b/components/native_viewport/platform_viewport_x11.cc
index bc240c9cec180bda7fa6da3ab5e7da7118b0757a..428a11f6538d503833e3bdfbc15f792dc2c61d39 100644
--- a/components/native_viewport/platform_viewport_x11.cc
+++ b/components/native_viewport/platform_viewport_x11.cc
@@ -12,7 +12,6 @@
 #include "ui/events/event.h"
 #include "ui/events/event_utils.h"
 #include "ui/events/platform/platform_event_dispatcher.h"
-#include "ui/events/platform/platform_event_source.h"
 #include "ui/gfx/geometry/rect.h"
 #include "ui/platform_window/platform_window.h"
 #include "ui/platform_window/platform_window_delegate.h"
@@ -45,11 +44,8 @@ class PlatformViewportX11 : public PlatformViewport,
  private:
   // Overridden from PlatformViewport:
   void Init(const gfx::Rect& bounds) override {
-    CHECK(!event_source_);
     CHECK(!platform_window_);
 
-    event_source_ = ui::PlatformEventSource::CreateDefault();
-
     metrics_ = mojo::ViewportMetrics::New();
     // TODO(sky): make density real.
     metrics_->device_pixel_ratio = 1.f;
@@ -154,7 +150,6 @@ class PlatformViewportX11 : public PlatformViewport,
 
   void OnActivationChanged(bool active) override {}
 
-  scoped_ptr<ui::PlatformEventSource> event_source_;
   scoped_ptr<ui::PlatformWindow> platform_window_;
   Delegate* delegate_;
   mojo::ViewportMetricsPtr metrics_;