[Autofill/Autocomplete Feature] Substring matching instead of prefix matching.

components/autofill/core/browser/personal_data_manager.cc

Index: components/autofill/core/browser/personal_data_manager.cc
diff --git a/components/autofill/core/browser/personal_data_manager.cc b/components/autofill/core/browser/personal_data_manager.cc
index 8b23c9266811e01d4f8347695a8af8bf65ca4fa3..41833839a0e6cd9177eb560f869287634754251c 100644
--- a/components/autofill/core/browser/personal_data_manager.cc
+++ b/components/autofill/core/browser/personal_data_manager.cc
@@ -29,6 +29,7 @@
 #include "components/autofill/core/browser/validation.h"
 #include "components/autofill/core/common/autofill_pref_names.h"
 #include "components/autofill/core/common/autofill_switches.h"
+#include "components/autofill/core/common/autofill_util.h"
 #include "components/signin/core/common/signin_pref_names.h"
 #include "third_party/libaddressinput/src/cpp/include/libaddressinput/address_data.h"
 #include "third_party/libaddressinput/src/cpp/include/libaddressinput/address_formatter.h"
@@ -830,6 +831,9 @@ std::vector<Suggestion> PersonalDataManager::GetProfileSuggestions(
   std::vector<Suggestion> suggestions;
   // Match based on a prefix search.
   std::vector<AutofillProfile*> matched_profiles;
+  std::vector<AutofillProfile*> substring_matched_profiles;
+  std::vector<base::string16> multi_values_for_substrings;
+  size_t prefix_match = 0;
   for (AutofillProfile* profile : profiles) {
     std::vector<base::string16> values =
         GetMultiInfoInOneLine(profile, type, app_locale_);
@@ -839,16 +843,30 @@ std::vector<Suggestion> PersonalDataManager::GetProfileSuggestions(
 
       base::string16 value_canon =
           AutofillProfile::CanonicalizeProfileString(values[i]);
+      // Order |profile|s with pre-fix before sub-string match.

[Evan Stade, 2015/03/24 00:48:26]

prefix, not pre-fix
substring, not sub-string

[Pritam Nikam, 2015/03/24 11:39:36]

Done.

       if (StartsWith(value_canon, field_contents_canon, true)) {
         // Prefix match, add suggestion.
         matched_profiles.push_back(profile);
         suggestions.push_back(Suggestion(values[i]));
         suggestions.back().backend_id.guid = profile->guid();
         suggestions.back().backend_id.variant = i;
+        ++prefix_match;
+      } else if (IsFeatureSubStringMatchEnabled() &&

[Evan Stade, 2015/03/24 00:48:26]

Substring (not SubString)

[Pritam Nikam, 2015/03/24 11:39:36]

Done.

+                 HasTokoneStartsWith(value_canon, field_contents_canon)) {
+        substring_matched_profiles.push_back(profile);

[Evan Stade, 2015/03/24 00:48:26]

add a field to Suggestion to indicate if it's a prefix match, sort suggestions 

[Pritam Nikam, 2015/03/24 11:39:36]

Done.

+        multi_values_for_substrings.push_back(values[i]);
       }
     }
   }
 
+  // Now append profiles having sub-string matching.
+  for (size_t k = 0; k < substring_matched_profiles.size(); k++) {
+    matched_profiles.push_back(substring_matched_profiles[k]);
+    suggestions.push_back(Suggestion(multi_values_for_substrings[k]));
+    suggestions.back().backend_id.guid = substring_matched_profiles[k]->guid();
+    suggestions.back().backend_id.variant = k + prefix_match;

[Evan Stade, 2015/03/24 00:48:26]

I do not understand this line at all

[Pritam Nikam, 2015/03/24 11:39:36]

substring matched suggestion's |backend_id.variant| are assigned with next index
in the suggestion list.

+  }
+
   // Don't show two suggestions if one is a subset of the other.
   std::vector<AutofillProfile*> unique_matched_profiles;
   std::vector<Suggestion> unique_suggestions;