Don't advertise that emails are generated by CakePHP.

Refs #5424

src/Network/Email/Email.php

@@ -45,13 +45,6 @@ class Email {
 	use StaticConfigTrait;
 
 /**
- * Default X-Mailer
- *
- * @var string
- */
-	const EMAIL_CLIENT = 'CakePHP Email';
-
-/**
  * Line length - no should more - RFC 2822 - 2.1.1
  *
  * @var int
@@ -787,9 +780,6 @@ class Email {
 		}
 
 		$headers += $this->_headers;
-		if (!isset($headers['X-Mailer'])) {
-			$headers['X-Mailer'] = static::EMAIL_CLIENT;
-		}
 		if (!isset($headers['Date'])) {
 			$headers['Date'] = date(DATE_RFC2822);
 		}

tests/TestCase/Network/Email/DebugTransportTest.php

@@ -50,13 +50,12 @@ class DebugTransportTest extends TestCase {
 		$email->messageID('<4d9946cf-0a44-4907-88fe-1d0ccbdd56cb@localhost>');
 		$email->subject('Testing Message');
 		$date = date(DATE_RFC2822);
-		$email->setHeaders(array('X-Mailer' => Email::EMAIL_CLIENT, 'Date' => $date));
+		$email->setHeaders(array('Date' => $date));
 		$email->expects($this->once())->method('message')->will($this->returnValue(array('First Line', 'Second Line', '.Third Line', '')));
 
 		$headers = "From: CakePHP Test <noreply@cakephp.org>\r\n";
 		$headers .= "To: CakePHP <cake@cakephp.org>\r\n";
 		$headers .= "Cc: Mark Story <mark@cakephp.org>, Juan Basso <juan@cakephp.org>\r\n";
-		$headers .= "X-Mailer: CakePHP Email\r\n";
 		$headers .= "Date: " . $date . "\r\n";
 		$headers .= "Message-ID: <4d9946cf-0a44-4907-88fe-1d0ccbdd56cb@localhost>\r\n";
 		$headers .= "Subject: Testing Message\r\n";

tests/TestCase/Network/Email/EmailTest.php

@@ -566,7 +566,6 @@ class EmailTest extends TestCase {
 		$this->CakeEmail->setHeaders(array('X-Something' => 'nice'));
 		$expected = array(
 			'X-Something' => 'nice',
-			'X-Mailer' => 'CakePHP Email',
 			'Date' => date(DATE_RFC2822),
 			'MIME-Version' => '1.0',
 			'Content-Type' => 'text/plain; charset=UTF-8',
@@ -578,7 +577,6 @@ class EmailTest extends TestCase {
 		$expected = array(
 			'X-Something' => 'very nice',
 			'X-Other' => 'cool',
-			'X-Mailer' => 'CakePHP Email',
 			'Date' => date(DATE_RFC2822),
 			'MIME-Version' => '1.0',
 			'Content-Type' => 'text/plain; charset=UTF-8',
@@ -593,7 +591,6 @@ class EmailTest extends TestCase {
 			'From' => 'cake@cakephp.org',
 			'X-Something' => 'very nice',
 			'X-Other' => 'cool',
-			'X-Mailer' => 'CakePHP Email',
 			'Date' => date(DATE_RFC2822),
 			'MIME-Version' => '1.0',
 			'Content-Type' => 'text/plain; charset=UTF-8',
@@ -611,7 +608,6 @@ class EmailTest extends TestCase {
 			'To' => 'cake@cakephp.org, CakePHP <php@cakephp.org>',
 			'X-Something' => 'very nice',
 			'X-Other' => 'cool',
-			'X-Mailer' => 'CakePHP Email',
 			'Date' => date(DATE_RFC2822),
 			'MIME-Version' => '1.0',
 			'Content-Type' => 'text/plain; charset=UTF-8',
@@ -625,7 +621,6 @@ class EmailTest extends TestCase {
 			'To' => 'cake@cakephp.org, CakePHP <php@cakephp.org>',
 			'X-Something' => 'very nice',
 			'X-Other' => 'cool',
-			'X-Mailer' => 'CakePHP Email',
 			'Date' => date(DATE_RFC2822),
 			'MIME-Version' => '1.0',
 			'Content-Type' => 'text/plain; charset=ISO-2022-JP',

tests/TestCase/Network/Email/SmtpTransportTest.php

@@ -380,7 +380,7 @@ class SmtpTransportTest extends TestCase {
 		$email->messageID('<4d9946cf-0a44-4907-88fe-1d0ccbdd56cb@localhost>');
 		$email->subject('Testing SMTP');
 		$date = date(DATE_RFC2822);
-		$email->setHeaders(array('X-Mailer' => Email::EMAIL_CLIENT, 'Date' => $date));
+		$email->setHeaders(array('Date' => $date));
 		$email->expects($this->once())
 			->method('message')
 			->will($this->returnValue(array('First Line', 'Second Line', '.Third Line', '')));
@@ -388,7 +388,6 @@ class SmtpTransportTest extends TestCase {
 		$data = "From: CakePHP Test <noreply@cakephp.org>\r\n";
 		$data .= "To: CakePHP <cake@cakephp.org>\r\n";
 		$data .= "Cc: Mark Story <mark@cakephp.org>, Juan Basso <juan@cakephp.org>\r\n";
-		$data .= "X-Mailer: CakePHP Email\r\n";
 		$data .= "Date: " . $date . "\r\n";
 		$data .= "Message-ID: <4d9946cf-0a44-4907-88fe-1d0ccbdd56cb@localhost>\r\n";
 		$data .= "Subject: Testing SMTP\r\n";