Customize: Prevent single quotes (apostrophes) in `custom_css` values from unexpectedly causing false positives for unbalanced character validation errors.

See #39218, #35395.
Fixes #39198.

Built from https://develop.svn.wordpress.org/trunk@39559


git-svn-id: http://core.svn.wordpress.org/trunk@39499 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/customize/class-wp-customize-custom-css-setting.php

@@ -191,13 +191,7 @@ final class WP_Customize_Custom_CSS_Setting extends WP_Customize_Setting {
 			$imbalanced = true;
 		}
 
-		// Ensure single quotes are equal.
-		if ( ! $this->validate_equal_characters( '\'', $css ) ) {
-			$validity->add( 'unequal_single_quotes', __( 'Your single quotes <code>\'</code> are uneven. Make sure there is a closing <code>\'</code> for every opening <code>\'</code>.' ) );
-			$imbalanced = true;
-		}
-
-		// Ensure single quotes are equal.
+		// Ensure double quotes are equal.
 		if ( ! $this->validate_equal_characters( '"', $css ) ) {
 			$validity->add( 'unequal_double_quotes', __( 'Your double quotes <code>"</code> are uneven. Make sure there is a closing <code>"</code> for every opening <code>"</code>.' ) );
 			$imbalanced = true;

wp-includes/version.php

@@ -4,7 +4,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '4.8-alpha-39558';
+$wp_version = '4.8-alpha-39559';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.