Mojo: Enable RemoteMessagePipeTest on Windows.

mojo/system/dispatcher.h

Index: mojo/system/dispatcher.h
diff --git a/mojo/system/dispatcher.h b/mojo/system/dispatcher.h
index b4cd526cf4eac3ac548a7b1f50e75cd68d8fe98b..309e2cd1249b9b12144466269a8d84d02c552616 100644
--- a/mojo/system/dispatcher.h
+++ b/mojo/system/dispatcher.h
@@ -30,10 +30,9 @@ class Waiter;
 
 namespace test {
 
-// Test helper.
-// TODO(vtl): We need to declare it here so we can friend it. We define it
-// inline below, but maybe it should be in a test-only file instead.
-DispatcherTransport DispatcherTryStartTransport(Dispatcher* dispatcher);
+// Test helper. We need to declare it here so we can friend it.
+MOJO_SYSTEM_IMPL_EXPORT DispatcherTransport DispatcherTryStartTransport(
+    Dispatcher* dispatcher);
 
 }  // namespace test
 
@@ -327,14 +326,6 @@ class MOJO_SYSTEM_IMPL_EXPORT DispatcherTransport {
   // Copy and assign allowed.
 };
 
-namespace test {
-
-inline DispatcherTransport DispatcherTryStartTransport(Dispatcher* dispatcher) {
-  return Dispatcher::CoreImplAccess::TryStartTransport(dispatcher);
-}
-
-}  // namespace test
-
 }  // namespace system
 }  // namespace mojo