Mojo EDK: Work around Nexus 9 hardware bug

mojo/edk/system/ports/node.cc

Index: mojo/edk/system/ports/node.cc
diff --git a/mojo/edk/system/ports/node.cc b/mojo/edk/system/ports/node.cc
index 93bb7c38b727ce0a6fd56d967b561b3409f052d8..d6e2767988c953b5ce20cec09d8a9e314bb2fc77 100644
--- a/mojo/edk/system/ports/node.cc
+++ b/mojo/edk/system/ports/node.cc
@@ -8,6 +8,7 @@
 
 #include <utility>
 
+#include "base/atomicops.h"
 #include "base/logging.h"
 #include "base/memory/ref_counted.h"
 #include "base/synchronization/lock.h"
@@ -808,6 +809,11 @@ scoped_refptr<Port> Node::GetPort_Locked(const PortName& port_name) {
   if (iter == ports_.end())
     return nullptr;
 
+#if defined(OS_ANDROID) && defined(ARCH_CPU_ARM64)
+  // Workaround for https://crbug.com/665869.
+  base::subtle::MemoryBarrier();
+#endif
+
   return iter->second;
 }