First step towards component build for Android.

base/android/base_jni_registrar.h

Index: base/android/base_jni_registrar.h
diff --git a/base/android/base_jni_registrar.h b/base/android/base_jni_registrar.h
index 678a3f3842775332ae66026906798e69b6112137..fdaf5f2c6cd7966dc77a426257888b4b46c38e6c 100644
--- a/base/android/base_jni_registrar.h
+++ b/base/android/base_jni_registrar.h
@@ -7,11 +7,13 @@
 
 #include <jni.h>
 
+#include "base/base_export.h"
+
 namespace base {
 namespace android {
 
 // Register all JNI bindings necessary for base.
-bool RegisterJni(JNIEnv* env);
+BASE_EXPORT bool RegisterJni(JNIEnv* env);
 
 }  // namespace android
 }  // namespace base