Add support for building the Dart VM for Android OS.

runtime/bin/eventhandler_android.h

Index: runtime/bin/eventhandler_android.h
diff --git a/runtime/bin/eventhandler_linux.h b/runtime/bin/eventhandler_android.h
similarity index 93%
copy from runtime/bin/eventhandler_linux.h
copy to runtime/bin/eventhandler_android.h
index 37e42aa3bbdafd3be1629de35dd13a469fc35da8..dfe2ff2ffe8ce41d07ff9ac858500507b55765b4 100644
--- a/runtime/bin/eventhandler_linux.h
+++ b/runtime/bin/eventhandler_android.h
@@ -2,11 +2,12 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-#ifndef BIN_EVENTHANDLER_LINUX_H_
-#define BIN_EVENTHANDLER_LINUX_H_
+#ifndef BIN_EVENTHANDLER_ANDROID_H_
+#define BIN_EVENTHANDLER_ANDROID_H_
 
 #if !defined(BIN_EVENTHANDLER_H_)
-#error Do not include eventhandler_linux.h directly; use eventhandler.h instead.
+#error Do not include eventhandler_android.h directly;
+#error use eventhandler.h instead.
 #endif
 
 #include <unistd.h>
@@ -118,4 +119,4 @@ class EventHandlerImplementation {
 };
 
 
-#endif  // BIN_EVENTHANDLER_LINUX_H_
+#endif  // BIN_EVENTHANDLER_ANDROID_H_