tty: don't read from console stream upon creation

The tty.ReadStream constructor initializes this as a socket,
which causes a read to be initiated. Even though during stdin
initalization we call readStop shortly after, the read operation
can consume keypress events from the system buffers.

Fixes: nodejs#5384

PR-URL: nodejs#5776
Reviewed-By: cjihrig - Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: jasnell - James M Snell <jasnell@gmail.com>

lib/tty.js

@@ -17,17 +17,23 @@ function ReadStream(fd, options) {
   if (!(this instanceof ReadStream))
     return new ReadStream(fd, options);
 
+  // pauseOnCreate to avoid reading from the sytem buffer
   options = util._extend({
     highWaterMark: 0,
     readable: true,
     writable: false,
-    handle: new TTY(fd, true)
+    handle: new TTY(fd, true),
+    pauseOnCreate: true
   }, options);
 
   net.Socket.call(this, options);
 
   this.isRaw = false;
   this.isTTY = true;
+
+  // Let the stream resume automatically when 'data' event handlers
+  // are added, even though it was paused on creation
+  this._readableState.flowing = null;
 }
 inherits(ReadStream, net.Socket);