[ci skip] Simplify some internal CI_Email code
diff --git a/system/libraries/Email.php b/system/libraries/Email.php
index d4b9387..0e9cf05 100644
--- a/system/libraries/Email.php
+++ b/system/libraries/Email.php
@@ -913,18 +913,13 @@
 	/**
 	 * Get Mail Protocol
 	 *
-	 * @param	bool
 	 * @return	mixed
 	 */
-	protected function _get_protocol($return = TRUE)
+	protected function _get_protocol()
 	{
 		$this->protocol = strtolower($this->protocol);
 		in_array($this->protocol, $this->_protocols, TRUE) OR $this->protocol = 'mail';
-
-		if ($return === TRUE)
-		{
-			return $this->protocol;
-		}
+		return $this->protocol;
 	}
 
 	// --------------------------------------------------------------------
@@ -932,10 +927,9 @@
 	/**
 	 * Get Mail Encoding
 	 *
-	 * @param	bool
 	 * @return	string
 	 */
-	protected function _get_encoding($return = TRUE)
+	protected function _get_encoding()
 	{
 		in_array($this->_encoding, $this->_bit_depths) OR $this->_encoding = '8bit';
 
@@ -947,10 +941,7 @@
 			}
 		}
 
-		if ($return === TRUE)
-		{
-			return $this->_encoding;
-		}
+		return $this->_encoding;
 	}
 
 	// --------------------------------------------------------------------
@@ -1829,14 +1820,15 @@
 	{
 		$this->_unwrap_specials();
 
-		$method = '_send_with_'.$this->_get_protocol();
+		$protocol = $this->_get_protocol();
+		$method   = '_send_with_'.$protocol;
 		if ( ! $this->$method())
 		{
-			$this->_set_error_message('lang:email_send_failure_'.($this->_get_protocol() === 'mail' ? 'phpmail' : $this->_get_protocol()));
+			$this->_set_error_message('lang:email_send_failure_'.($protocol === 'mail' ? 'phpmail' : $protocol));
 			return FALSE;
 		}
 
-		$this->_set_error_message('lang:email_sent', $this->_get_protocol());
+		$this->_set_error_message('lang:email_sent', $protocol);
 		return TRUE;
 	}