x11: Move X event handling out of the message-pump.

ash/drag_drop/drag_drop_interactive_uitest.cc

Index: ash/drag_drop/drag_drop_interactive_uitest.cc
diff --git a/ash/drag_drop/drag_drop_interactive_uitest.cc b/ash/drag_drop/drag_drop_interactive_uitest.cc
index f9b3ceeb1c7801d8ddb2cef30f541aac873fa7a0..bd040ed7ad87f03b597648dd28d034f5db284e04 100644
--- a/ash/drag_drop/drag_drop_interactive_uitest.cc
+++ b/ash/drag_drop/drag_drop_interactive_uitest.cc
@@ -15,6 +15,7 @@
 #include "ui/base/resource/resource_bundle.h"
 #include "ui/base/test/ui_controls.h"
 #include "ui/base/ui_base_paths.h"
+#include "ui/events/platform/platform_event_source.h"
 #include "ui/gl/gl_surface.h"
 #include "ui/views/view.h"
 #include "ui/views/widget/widget.h"
@@ -139,8 +140,14 @@ class DragDropTest : public test::AshTestBase {
     ResourceBundle::GetSharedInstance().AddDataPackFromPath(
         resources_pack_path, ui::SCALE_FACTOR_NONE);
 
+    event_source_ = ui::PlatformEventSource::CreateDefault();
     test::AshTestBase::SetUp();
   }
+
+ private:
+  scoped_ptr<ui::PlatformEventSource> event_source_;
+
+  DISALLOW_COPY_AND_ASSIGN(DragDropTest);
 };
 
 #if defined(OS_WIN)