Also make eventhandler on Android edge-triggered.

runtime/bin/eventhandler_linux.cc

Index: runtime/bin/eventhandler_linux.cc
diff --git a/runtime/bin/eventhandler_linux.cc b/runtime/bin/eventhandler_linux.cc
index 28298c093a5adc8a2592e7c9aa4e729e084e7e6f..c6ebc335fa0b5ffd8f7fd7b82ced205b37aef4cf 100644
--- a/runtime/bin/eventhandler_linux.cc
+++ b/runtime/bin/eventhandler_linux.cc
@@ -24,7 +24,6 @@
 #include "platform/hashmap.h"
 #include "platform/thread.h"
 #include "platform/utils.h"
-#include "vm/thread.h"
 
 
 namespace dart {
@@ -249,9 +248,7 @@ intptr_t EventHandlerImplementation::GetPollEvents(intptr_t events,
     // other flags.
     if ((events & EPOLLIN) != 0) {
       if ((events & EPOLLHUP) != 0) event_mask |= (1 << kCloseEvent);
-      if ((events & EPOLLERR) != 0) {
-        event_mask |= (1 << kErrorEvent);
-      }
+      if ((events & EPOLLERR) != 0) event_mask |= (1 << kErrorEvent);
       if (event_mask == 0) event_mask |= (1 << kInEvent);
     }
   } else {