Cleanup: Pass std::string as const reference from components/

components/url_matcher/url_matcher_unittest.cc

Index: components/url_matcher/url_matcher_unittest.cc
diff --git a/components/url_matcher/url_matcher_unittest.cc b/components/url_matcher/url_matcher_unittest.cc
index 328c633c311207d04610f29744eab87c61b0d791..3d6d6c5c753433cb449e1179ada8d08842b0b285 100644
--- a/components/url_matcher/url_matcher_unittest.cc
+++ b/components/url_matcher/url_matcher_unittest.cc
@@ -147,7 +147,7 @@ TEST(URLMatcherConditionTest, Comparison) {
 
 namespace {
 
-bool Matches(const URLMatcherCondition& condition, std::string text) {
+bool Matches(const URLMatcherCondition& condition, const std::string& text) {
   return text.find(condition.string_pattern()->pattern()) !=
       std::string::npos;
 }