RPC: Initialize lastUsedTime to after the conn has been initialized.
This prevents it from seeming idle as soon as it has been created.

Change-Id: If2d6be8e9fbbedd5234de43159c5377629c528be
diff --git a/runtime/internal/flow/conn/conn.go b/runtime/internal/flow/conn/conn.go
index 29b833a..b8723a6 100644
--- a/runtime/internal/flow/conn/conn.go
+++ b/runtime/internal/flow/conn/conn.go
@@ -228,6 +228,10 @@
 	}
 	c.loopWG.Add(1)
 	go c.readLoop(ctx)
+
+	c.mu.Lock()
+	c.lastUsedTime = time.Now()
+	c.mu.Unlock()
 	return c, names, rejected, nil
 }
 
@@ -297,6 +301,9 @@
 	c.loopWG.Add(2)
 	go c.blessingsLoop(ctx, refreshTime, lAuthorizedPeers)
 	go c.readLoop(ctx)
+	c.mu.Lock()
+	c.lastUsedTime = time.Now()
+	c.mu.Unlock()
 	return c, nil
 }