Add an AutofillProfileComparator class.

components/autofill/core/browser/autofill_profile.h

Index: components/autofill/core/browser/autofill_profile.h
diff --git a/components/autofill/core/browser/autofill_profile.h b/components/autofill/core/browser/autofill_profile.h
index 3f5e1eedd8616e5394e5eb8271a78cc5871c9e14..7ab0ac2722d8b610a4ee4d5c46fe83f91d4e36bb 100644
--- a/components/autofill/core/browser/autofill_profile.h
+++ b/components/autofill/core/browser/autofill_profile.h
@@ -186,11 +186,6 @@ class AutofillProfile : public AutofillDataModel {
   // for storing or displaying to the user.
   static base::string16 CanonicalizeProfileString(const base::string16& str);
 
-  // Returns true if the given two profile strings are similar enough that
-  // they probably refer to the same thing.
-  static bool AreProfileStringsSimilar(const base::string16& a,
-                                       const base::string16& b);
-
  private:
   typedef std::vector<const FormGroup*> FormGroupList;