streams2: Call read(0) on resume()

Otherwise (especially with stdin) you sometimes end up in cases
where the high water mark is zero, and the current buffer is at 0,
and it doesn't need a readable event, so it never calls _read().

lib/_debugger.js

@@ -36,7 +36,7 @@ exports.start = function(argv, stdin, stdout) {
   }
 
   // Setup input/output streams
-  stdin = stdin || process.openStdin();
+  stdin = stdin || process.stdin;
   stdout = stdout || process.stdout;
 
   var args = ['--debug-brk'].concat(argv),

lib/_stream_readable.js

@@ -521,6 +521,7 @@ Readable.prototype.addListener = Readable.prototype.on;
 // If the user uses them, then switch into old mode.
 Readable.prototype.resume = function() {
   emitDataEvents(this);
+  this.read(0);
 };
 
 Readable.prototype.pause = function() {
@@ -566,6 +567,8 @@ function emitDataEvents(stream, startPaused) {
       process.nextTick(function() {
         stream.emit('readable');
       });
+    else
+      this.read(0);
   };
 
   // now make it start, just in case it hadn't already.