Restructure the events target into two components:

ui/events/event_switches.h

Index: ui/events/event_switches.h
diff --git a/ui/events/event_switches.h b/ui/events/event_switches.h
index ec2fbd197f72dc1f83bd4d722923cc52faf5f00a..d4343046e5034c5ef04d685fe3974b2c6a09c8f5 100644
--- a/ui/events/event_switches.h
+++ b/ui/events/event_switches.h
@@ -6,18 +6,18 @@
 #define UI_EVENTS_EVENTS_SWITCHES_H_
 
 #include "base/compiler_specific.h"
-#include "ui/events/events_export.h"
+#include "ui/events/events_base_export.h"
 
 namespace switches {
 
-EVENTS_EXPORT extern const char kEnableScrollPrediction[];
-EVENTS_EXPORT extern const char kTouchEvents[];
-EVENTS_EXPORT extern const char kTouchEventsAuto[];
-EVENTS_EXPORT extern const char kTouchEventsEnabled[];
-EVENTS_EXPORT extern const char kTouchEventsDisabled[];
+EVENTS_BASE_EXPORT extern const char kEnableScrollPrediction[];
+EVENTS_BASE_EXPORT extern const char kTouchEvents[];
+EVENTS_BASE_EXPORT extern const char kTouchEventsAuto[];
+EVENTS_BASE_EXPORT extern const char kTouchEventsEnabled[];
+EVENTS_BASE_EXPORT extern const char kTouchEventsDisabled[];
 
 #if defined(OS_LINUX)
-EVENTS_EXPORT extern const char kTouchDevices[];
+EVENTS_BASE_EXPORT extern const char kTouchDevices[];
 #endif
 
 }  // namespace switches