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

components/autofill/core/browser/suggestion.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "components/autofill/core/browser/suggestion.h"
 
 #include "base/strings/utf_string_conversions.h"
 #include "components/autofill/core/browser/autofill_profile.h"
 #include "components/autofill/core/browser/credit_card.h"
 
 namespace autofill {
 
 Suggestion::Suggestion()
-    : frontend_id(0) {
+    : frontend_id(0),
+      match(PREFIX_MATCH) {
 }
 
 Suggestion::Suggestion(const Suggestion& other)
     : backend_id(other.backend_id),
       frontend_id(other.frontend_id),
       value(other.value),
       label(other.label),
-      icon(other.icon) {
+      icon(other.icon),
+      match(other.match) {
 }
 
 Suggestion::Suggestion(const base::string16& v)
     : frontend_id(0),
-      value(v) {
+      value(v),
+      match(PREFIX_MATCH) {
 }
 
 Suggestion::Suggestion(const std::string& v,
                        const std::string& l,
                        const std::string& i,
                        int fid)
     : frontend_id(fid),
       value(base::UTF8ToUTF16(v)),
       label(base::UTF8ToUTF16(l)),
-      icon(base::UTF8ToUTF16(i)) {
+      icon(base::UTF8ToUTF16(i)),
+      match(PREFIX_MATCH) {
 }
 
 Suggestion::~Suggestion() {
 }
 
+void OrderPrefixBeforeSubstring(std::vector<Suggestion>* suggestions) {
+  std::sort(suggestions->begin(), suggestions->end(),
+            [](const Suggestion& s1, const Suggestion& s2) {
+              return s1.match < s2.match;

[Evan Stade, 2015/06/08 23:23:38]

You probably want std::stable_sort (because we don't want to clobber the
ordering that otherwise exists, i.e. MFU).

[Evan Stade, 2015/06/08 23:24:34]

actually, I would suggest just extending OrderByMfu to also consider the match
type.

[Pritam Nikam, 2015/06/09 11:39:06]

Done.

[Pritam Nikam, 2015/06/09 11:39:06]

Did you mean RankByMfu (Ref [1])?
This API does sort profiles (i.e. AutofillDataModel) and not the suggestion
(struct Suggestion). Adding match type check does not seem right to me.

[1].
https://code.google.com/p/chromium/codesearch#chromium/src/components/autofil...

+            });
+}
+
 }  // namespace autofill