Email message charset setup added.

framework/yii/mail/BaseMessage.php

@@ -21,6 +21,7 @@ use Yii;
  * @see BaseMailer
  *
  * @property \yii\mail\BaseMailer $mailer mailer component instance. This property is read-only.
+ * @property string $charset the character set of this message.
  * @property string|array $from sender email address.
  * @property string|array $to receiver email address.
  * @property string|array $cc copy receiver email address.

framework/yii/mail/MessageInterface.php

@@ -15,6 +15,12 @@ namespace yii\mail;
  */
 interface MessageInterface
 {
+	/**
+	 * Set the character set of this message.
+	 * @param string $charset character set name.
+	 */
+	public function setCharset($charset);
+
 	/**
 	 * Sets message sender.
 	 * @param string|array $from sender email address.