Avoiding Vectors usage while setting info in AutofillProfile.

components/autofill/core/browser/webdata/autofill_table.cc

Index: components/autofill/core/browser/webdata/autofill_table.cc
diff --git a/components/autofill/core/browser/webdata/autofill_table.cc b/components/autofill/core/browser/webdata/autofill_table.cc
index b9468bb2a51ddec27b3c3692b6f593ea57909492..c337f60223f165cecc20a75e0ae7808ddaf7f800 100644
--- a/components/autofill/core/browser/webdata/autofill_table.cc
+++ b/components/autofill/core/browser/webdata/autofill_table.cc
@@ -191,90 +191,68 @@ scoped_ptr<CreditCard> CreditCardFromStatement(const sql::Statement& s) {
 
 bool AddAutofillProfileNamesToProfile(sql::Connection* db,
                                       AutofillProfile* profile) {
+  // TODO(estade): update schema so that multiple names are not associated per
+  // unique profile guid. Please refer https://crbug.com/497934.
   sql::Statement s(db->GetUniqueStatement(
       "SELECT guid, first_name, middle_name, last_name, full_name "
       "FROM autofill_profile_names "
-      "WHERE guid=?"));
+      "WHERE guid=?"
+      "LIMIT 1"));

[Scott Hess - ex-Googler, 2015/08/12 21:31:29]

Note that if you have multiple items with the same GUID, without an ORDER BY
clause there is no guarantee that the first result will be the same each time. 
In practice a given release of SQLite is likely to return results in the same
implementation-defined order from run to run.  This can lead to problems like
bug 412968, where a new SQLite implementation did not return things in the same
order as the old one (in fact, in some cases the GUID meant that the order was
not stable between runs of the tests).

Since the set of items matching GUID is probably tiny, I'd probably go with
ORDER BY 2, 3, 4, 5 or something of the sort, just to make it the same each
time.  If the guid is indexed, the performance difference will probably not be
measurable.

Of course, this isn't really a problem with this CL, it was present in the
earlier code.  It's more of a hygiene consideration.

   s.BindString(0, profile->guid());
 
   if (!s.is_valid())
     return false;
 
-  std::vector<base::string16> first_names;
-  std::vector<base::string16> middle_names;
-  std::vector<base::string16> last_names;
-  std::vector<base::string16> full_names;
-  while (s.Step()) {
+  if (s.Step()) {
     DCHECK_EQ(profile->guid(), s.ColumnString(0));
-    first_names.push_back(s.ColumnString16(1));
-    middle_names.push_back(s.ColumnString16(2));
-    last_names.push_back(s.ColumnString16(3));
-    full_names.push_back(s.ColumnString16(4));
+    profile->SetRawInfo(NAME_FIRST, s.ColumnString16(1));
+    profile->SetRawInfo(NAME_MIDDLE, s.ColumnString16(2));
+    profile->SetRawInfo(NAME_LAST, s.ColumnString16(3));
+    profile->SetRawInfo(NAME_FULL, s.ColumnString16(4));
   }
-  if (!s.Succeeded())
-    return false;
-
-  // TODO(estade): update schema so these aren't vectors.
-  first_names.resize(1);
-  middle_names.resize(1);
-  last_names.resize(1);
-  full_names.resize(1);
-
-  profile->SetRawInfo(NAME_FIRST, first_names[0]);
-  profile->SetRawInfo(NAME_MIDDLE, middle_names[0]);
-  profile->SetRawInfo(NAME_LAST, last_names[0]);
-  profile->SetRawInfo(NAME_FULL, full_names[0]);
-  return true;
+  return s.Succeeded();
 }
 
 bool AddAutofillProfileEmailsToProfile(sql::Connection* db,
                                        AutofillProfile* profile) {
+  // TODO(estade): update schema so that multiple emails are not associated per
+  // unique profile guid. Please refer https://crbug.com/497934.
   sql::Statement s(db->GetUniqueStatement(
       "SELECT guid, email "
       "FROM autofill_profile_emails "
-      "WHERE guid=?"));
+      "WHERE guid=?"
+      "LIMIT 1"));
   s.BindString(0, profile->guid());
 
   if (!s.is_valid())
     return false;
 
-  std::vector<base::string16> emails;
-  while (s.Step()) {
+  if (s.Step()) {
     DCHECK_EQ(profile->guid(), s.ColumnString(0));
-    emails.push_back(s.ColumnString16(1));
+    profile->SetRawInfo(EMAIL_ADDRESS, s.ColumnString16(1));
   }
-  if (!s.Succeeded())
-    return false;
-
-  // TODO(estade): update schema so this is not a vector.
-  emails.resize(1);
-  profile->SetRawInfo(EMAIL_ADDRESS, emails[0]);
-  return true;
+  return s.Succeeded();
 }
 
 bool AddAutofillProfilePhonesToProfile(sql::Connection* db,
                                        AutofillProfile* profile) {
+  // TODO(estade): update schema so that multiple phone numbers are not
+  // associated per unique profile guid. Please refer https://crbug.com/497934.
   sql::Statement s(db->GetUniqueStatement(
       "SELECT guid, number "
       "FROM autofill_profile_phones "
-      "WHERE guid=?"));
+      "WHERE guid=?"
+      "LIMIT 1"));
   s.BindString(0, profile->guid());
 
   if (!s.is_valid())
     return false;
 
-  std::vector<base::string16> numbers;
-  while (s.Step()) {
+  if (s.Step()) {
     DCHECK_EQ(profile->guid(), s.ColumnString(0));
-    numbers.push_back(s.ColumnString16(1));
+    profile->SetRawInfo(PHONE_HOME_WHOLE_NUMBER, s.ColumnString16(1));
   }
-  if (!s.Succeeded())
-    return false;
-
-  // TODO(estade): update schema so this isn't a vector.
-  numbers.resize(1);
-  profile->SetRawInfo(PHONE_HOME_WHOLE_NUMBER, numbers[0]);
-  return true;
+  return s.Succeeded();
 }
 
 bool AddAutofillProfileNames(const AutofillProfile& profile,