Coding Standards: Rename $d parameter in various date/time functions to $format for clarity.

See #49222.
Built from https://develop.svn.wordpress.org/trunk@47287


git-svn-id: http://core.svn.wordpress.org/trunk@47087 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-admin/includes/image.php

@@ -638,9 +638,9 @@ function wp_exif_frac2dec( $str ) {
 		return $str;
 	}
 
-	list( $n, $d ) = explode( '/', $str );
-	if ( ! empty( $d ) ) {
-		return $n / $d;
+	list( $numerator, $denominator ) = explode( '/', $str );
+	if ( ! empty( $denominator ) ) {
+		return $numerator / $denominator;
 	}
 	return $str;
 }