Correctly encode spaces in URLs passed to `esc_url()` instead of removing them.

Fixes #23605
Props enshrined, johnbillion

Built from https://develop.svn.wordpress.org/trunk@33858


git-svn-id: http://core.svn.wordpress.org/trunk@33826 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/formatting.php

@@ -3274,11 +3274,14 @@ function esc_url( $url, $protocols = null, $_context = 'display' ) {
 
 	if ( '' == $url )
 		return $url;
+
+	$url = str_replace( ' ', '%20', $url );
 	$url = preg_replace('|[^a-z0-9-~+_.?#=!&;,/:%@$\|*\'()\\x80-\\xff]|i', '', $url);
 	if ( 0 !== stripos( $url, 'mailto:' ) ) {
 		$strip = array('%0d', '%0a', '%0D', '%0A');
 		$url = _deep_replace($strip, $url);
 	}
+
 	$url = str_replace(';//', '://', $url);
 	/* If the URL doesn't appear to contain a scheme, we
 	 * presume it needs http:// appended (unless a relative

wp-includes/version.php

@@ -4,7 +4,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '4.4-alpha-33857';
+$wp_version = '4.4-alpha-33858';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.