First step towards component build for Android.

base/message_pump_android.h

Index: base/message_pump_android.h
diff --git a/base/message_pump_android.h b/base/message_pump_android.h
index 10a55826d46f3ecd909e4f6f044658780883d7e2..5ef4bd6920380a9f8daeea197807a27f19dc1c08 100644
--- a/base/message_pump_android.h
+++ b/base/message_pump_android.h
@@ -7,6 +7,7 @@
 
 #include <jni.h>
 
+#include "base/base_export.h"
 #include "base/compiler_specific.h"
 #include "base/message_pump.h"
 
@@ -17,7 +18,7 @@ class TimeTicks;
 
 // This class implements a MessagePump needed for TYPE_UI MessageLoops on
 // OS_ANDROID platform.
-class MessagePumpForUI : public MessagePump {
+class BASE_EXPORT MessagePumpForUI : public MessagePump {
  public:
   MessagePumpForUI();