[Autofill] Dedupe similar profiles on insertion.

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..65cf6a9d3f3dbba6d9515e8bffa4fa1be7c7968e 100644
--- a/components/autofill/core/browser/autofill_profile.h
+++ b/components/autofill/core/browser/autofill_profile.h
@@ -99,9 +99,10 @@ class AutofillProfile : public AutofillDataModel {
   bool operator==(const AutofillProfile& profile) const;
   virtual bool operator!=(const AutofillProfile& profile) const;
 
-  // Returns concatenation of first name, last name, address line 1 and city.
-  // This acts as the basis of comparison for new values that are submitted
-  // through forms to aid with correct aggregation of new data.
+  // Returns concatenation of first name, last name, address line 1 and city,
+  // with each part separated by a whitespace. This acts as the basis of
+  // comparison for new values that are submitted through forms to aid with
+  // correct aggregation of new data.
   const base::string16 PrimaryValue() const;
 
   // Returns true if the data in this AutofillProfile is a subset of the data in