Fix whitespace being reported as method caller

When a method call was wrapped to another line, the whitespace in front of it would be reported as the caller, instead of the correct variable or `(unknown)`.

Fixes #31

(cherry picked from commit 5faaf63)

tests/data/class-method-names.php

@@ -56,6 +56,13 @@ function inner_func( _debug_ ) {}
 
 get_some_class()->method( _debug_ );
 
+wordpoints_component( $var )
+	->get_sub_app( $var )
+	->get_sub_app( _debug_ );
+
+$var
+	->wrap( _debug_ );
+
 interface ParentI {
 	public function parent_method( $var _debug_ );
 }

tests/tests/class-method-names.php

@@ -72,6 +72,8 @@ public function test_class_method_names() {
 			'$wpdb->query',
 			'WP_Query::__construct',
 			'(unknown)->method',
+			'(unknown)->get_sub_app',
+			'$var->wrap',
 			'ParentI::parent_method',
 			'ChildI::ignored',
 			'Implementor::parent_method',

wp-l10n-validator.php

@@ -1033,8 +1033,17 @@ private function _parse_string( $content ) {
 
 								case '::':
 								case '->':
-									if ( isset( $tokens[ $index - 2 ][1] ) ) {
-										switch ( $tokens[ $index - 2 ][1] ) {
+									$caller_index = $index - 2;
+
+									if (
+										isset( $tokens[ $caller_index ][0] )
+										&& T_WHITESPACE === $tokens[ $caller_index ][0]
+									) {
+										$caller_index -= 1;
+									}
+
+									if ( isset( $tokens[ $caller_index ][1] ) ) {
+										switch ( $tokens[ $caller_index ][1] ) {
 
 											case 'self':
 											case '$this':
@@ -1055,7 +1064,7 @@ private function _parse_string( $content ) {
 											// fallthru
 
 											default:
-												$full_function = $tokens[ $index - 2 ][1] . $tokens[ $index - 1 ][1] . $full_function;
+												$full_function = $tokens[ $caller_index ][1] . $tokens[ $index - 1 ][1] . $full_function;
 										}
 
 									} else {