autofill: switch autofill_regexes to RE2 library

components/autofill/core/common/autofill_regexes.h

Index: components/autofill/core/common/autofill_regexes.h
diff --git a/components/autofill/core/common/autofill_regexes.h b/components/autofill/core/common/autofill_regexes.h
index 1bf1aa73a6c51b9158a86d1e2e3185591f510e50..71670755766616d8661806e5ab9361ca89b423b8 100644
--- a/components/autofill/core/common/autofill_regexes.h
+++ b/components/autofill/core/common/autofill_regexes.h
@@ -5,15 +5,13 @@
 #ifndef COMPONENTS_AUTOFILL_CORE_COMMON_AUTOFILL_REGEXES_H_
 #define COMPONENTS_AUTOFILL_CORE_COMMON_AUTOFILL_REGEXES_H_
 
-#include "base/strings/string16.h"
+#include <string>
 
-// Parsing utilities.
 namespace autofill {
 
 // Case-insensitive regular expression matching.
 // Returns true if |pattern| is found in |input|.
-bool MatchesPattern(const base::string16& input,
-                    const base::string16& pattern);
+bool MatchesPattern(const std::string& input, const std::string& pattern);
 
 }  // namespace autofill