Coding Standards: Use strict comparison in wp-includes/class-wp-image-editor.php.

Follow-up to [22094].

Props aristath, poena, afercia, SergeyBiryukov.
See #58831.

git-svn-id: https://develop.svn.wordpress.org/trunk@56361 602fd350-edb4-49c9-b593-d223f7449a82

Author: SergeyBiryukov

src/wp-includes/class-wp-image-editor.php

@@ -353,7 +353,7 @@ protected function get_output_format( $filename = null, $mime_type = null ) {
 		 * Check to see if specified mime-type is the same as type implied by
 		 * file extension. If so, prefer extension from file.
 		 */
-		if ( ! $mime_type || ( $file_mime == $mime_type ) ) {
+		if ( ! $mime_type || ( $file_mime === $mime_type ) ) {
 			$mime_type = $file_mime;
 			$new_ext   = $file_ext;
 		}