Revert "When connection fail, emit the error. (brianc#28)"

This reverts commit 6a7edab.

The callback passed to `Pool.prototype.connect` should be responsible for handling connection errors. The `error` event is documented to be:

> Emitted whenever an idle client in the pool encounters an error.

This isn’t the case of an idle client in the pool; it never makes it into the pool.

It also breaks tests on pg’s master because of nonspecific dependencies.

index.js

@@ -43,7 +43,6 @@ Pool.prototype._create = function (cb) {
     if (err) {
       this.log('client connection error:', err)
       cb(err)
-      this.emit('error', err)
     } else {
       this.log('client connected')
       this.emit('connect', client)

test/events.js

@@ -22,7 +22,7 @@ describe('events', function () {
     })
   })
 
-  it('emits "error" with a failed connection', function (done) {
+  it('emits "connect" only with a successful connection', function (done) {
     var pool = new Pool({
       // This client will always fail to connect
       Client: mockClient({
@@ -34,29 +34,7 @@ describe('events', function () {
     pool.on('connect', function () {
       throw new Error('should never get here')
     })
-    pool.on('error', function (err) {
-      if (err) done()
-      else done(new Error('expected failure'))
-    })
-    pool.connect()
-  })
-
-  it('callback err with a failed connection', function (done) {
-    var pool = new Pool({
-      // This client will always fail to connect
-      Client: mockClient({
-        connect: function (cb) {
-          process.nextTick(function () { cb(new Error('bad news')) })
-        }
-      })
-    })
-    pool.on('connect', function () {
-      throw new Error('should never get here')
-    })
-    pool.on('error', function (err) {
-      if (!err) done(new Error('expected failure'))
-    })
-    pool.connect(function (err) {
+    pool._create(function (err) {
       if (err) done()
       else done(new Error('expected failure'))
     })