Enables the user to select multiple languages for spellchecking (UI)

chrome/browser/spellchecker/spellcheck_service.cc

Index: chrome/browser/spellchecker/spellcheck_service.cc
diff --git a/chrome/browser/spellchecker/spellcheck_service.cc b/chrome/browser/spellchecker/spellcheck_service.cc
index a0411012c86d26c1162e74392ba5301dd821b813..a016149dad448144532ab7e78360fbc37d6d6f44 100644
--- a/chrome/browser/spellchecker/spellcheck_service.cc
+++ b/chrome/browser/spellchecker/spellcheck_service.cc
@@ -4,6 +4,7 @@
 
 #include "chrome/browser/spellchecker/spellcheck_service.h"
 
+#include "base/command_line.h"
 #include "base/prefs/pref_member.h"
 #include "base/prefs/pref_service.h"
 #include "base/strings/string_split.h"
@@ -13,6 +14,7 @@
 #include "chrome/browser/spellchecker/spellcheck_hunspell_dictionary.h"
 #include "chrome/browser/spellchecker/spellcheck_platform_mac.h"
 #include "chrome/browser/spellchecker/spelling_service_client.h"
+#include "chrome/common/chrome_switches.h"
 #include "chrome/common/pref_names.h"
 #include "chrome/common/spellcheck_messages.h"
 #include "components/user_prefs/user_prefs.h"
@@ -84,20 +86,32 @@ SpellcheckService::~SpellcheckService() {
 }
 
 // static
-int SpellcheckService::GetSpellCheckLanguages(
+std::set<int> SpellcheckService::GetSpellCheckLanguages(
     content::BrowserContext* context,
     std::vector<std::string>* languages) {
   PrefService* prefs = user_prefs::UserPrefs::Get(context);
-  StringPrefMember accept_languages_pref;
-  StringPrefMember dictionary_language_pref;
-  accept_languages_pref.Init(prefs::kAcceptLanguages, prefs);
-  dictionary_language_pref.Init(prefs::kSpellCheckDictionary, prefs);
-  std::string dictionary_language = dictionary_language_pref.GetValue();
 
-  // Now scan through the list of accept languages, and find possible mappings
-  // from this list to the existing list of spell check languages.
+  std::vector<std::string> dictionary_languages;
+
+  const CommandLine* command_line = CommandLine::ForCurrentProcess();
+  if (command_line->HasSwitch(switches::kEnableMultilingualSpellChecker)) {
+    StringPrefMember dictionary_languages_pref;
+    dictionary_languages_pref.Init(prefs::kSpellCheckDictionaries, prefs);
+
+    base::SplitString(
+        dictionary_languages_pref.GetValue(), ',', &dictionary_languages);
+  } else {
+    StringPrefMember dictionary_language_pref;
+    dictionary_language_pref.Init(prefs::kSpellCheckDictionary, prefs);
+
+    dictionary_languages.push_back(dictionary_language_pref.GetValue());
+  }
+
   std::vector<std::string> accept_languages;
 
+  StringPrefMember accept_languages_pref;
+  accept_languages_pref.Init(prefs::kAcceptLanguages, prefs);
+
 #if defined(OS_MACOSX)
   if (spellcheck_mac::SpellCheckerAvailable())
     spellcheck_mac::GetAvailableLanguages(&accept_languages);
@@ -107,24 +121,20 @@ int SpellcheckService::GetSpellCheckLanguages(
   base::SplitString(accept_languages_pref.GetValue(), ',', &accept_languages);
 #endif  // !OS_MACOSX
 
-  GetSpellCheckLanguagesFromAcceptLanguages(
-      accept_languages, dictionary_language, languages);
+  // Put the currently selected languages as first ones on the list
+  *languages = dictionary_languages;
+  GetSpellCheckLanguagesFromAcceptLanguages(accept_languages, languages);
 
-  for (size_t i = 0; i < languages->size(); ++i) {
-    if ((*languages)[i] == dictionary_language)
-      return i;
-  }
-  return -1;
+  std::set<int> selected_languages;
+  for (size_t i = 0; i < dictionary_languages.size(); ++i)
+    selected_languages.insert(i);
+  return selected_languages;
 }
 
 // static
 void SpellcheckService::GetSpellCheckLanguagesFromAcceptLanguages(
     const std::vector<std::string>& accept_languages,
-    const std::string& dictionary_language,
     std::vector<std::string>* languages) {
-  // The current dictionary language should be there.
-  languages->push_back(dictionary_language);
-
   for (std::vector<std::string>::const_iterator i = accept_languages.begin();
        i != accept_languages.end(); ++i) {
     std::string language =