Revert "net: Avoid tickDepth warnings on small writes"

This commit breaks simple/test-stream2-stderr-sync.  Need to figure out
a better way, or just accept that `(function W(){stream.write(b,W)})()`
is going to be noisy.  People should really be using the `'drain'` event
for this use-case anyway.

This reverts commit 02f7d1bfd8.

lib/net.js

@@ -601,8 +601,14 @@ Socket.prototype._write = function(dataEncoding, cb) {
     return this._destroy(errnoException(errno, 'write'), cb);
 
   writeReq.oncomplete = afterWrite;
-  writeReq.cb = cb;
   this._bytesDispatched += writeReq.bytes;
+
+  // If it was entirely flushed, we can write some more right now.
+  // However, if more is left in the queue, then wait until that clears.
+  if (this._handle.writeQueueSize === 0)
+    cb();
+  else
+    writeReq.cb = cb;
 };
 
 function createWriteReq(handle, data, encoding) {

test/simple/test-net-many-small-writes.js

@@ -1,84 +0,0 @@
-// Copyright Joyent, Inc. and other Node contributors.
-//
-// Permission is hereby granted, free of charge, to any person obtaining a
-// copy of this software and associated documentation files (the
-// "Software"), to deal in the Software without restriction, including
-// without limitation the rights to use, copy, modify, merge, publish,
-// distribute, sublicense, and/or sell copies of the Software, and to permit
-// persons to whom the Software is furnished to do so, subject to the
-// following conditions:
-//
-// The above copyright notice and this permission notice shall be included
-// in all copies or substantial portions of the Software.
-//
-// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
-// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
-// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
-// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
-// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
-// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
-// USE OR OTHER DEALINGS IN THE SOFTWARE.
-
-var common = require('../common');
-var assert = require('assert');
-
-// make sure we get no tickDepth warnings.
-
-if (process.argv[2] === 'child')
-  child();
-else
-  parent();
-
-function parent() {
-  var spawn = require('child_process').spawn;
-  var node = process.execPath;
-  var child = spawn(node, [__filename, 'child']);
-
-  child.stdout.pipe(process.stdout);
-
-  child.stderr.setEncoding('utf8');
-  var err = '';
-  child.stderr.on('data', function(c) {
-    err += c;
-  });
-  var gotClose = false;
-  child.on('close', function(code) {
-    assert(!code);
-    assert.equal(err, '');
-    gotClose = true;
-  });
-  process.on('exit', function() {
-    assert(gotClose);
-    console.log('PARENT: ok');
-  });
-}
-
-function child() {
-  var net = require('net');
-  process.maxTickDepth = 10;
-  var server = net.createServer(function(sock) {
-    var i = 0;
-    w();
-    function w() {
-      if (++i < 100)
-        sock.write(new Buffer(1), w);
-      else
-        sock.end();
-    }
-  });
-  server.listen(common.PORT);
-
-  var finished = false;
-  var client = net.connect(common.PORT);
-  client.resume();
-  client.on('end', function() {
-    server.close(function() {
-      finished = true;
-    });
-  });
-
-  process.on('exit', function() {
-    assert(finished);
-    console.log('CHILD: ok');
-  });
-}