Language.{h,cpp} clean-up.

- Remove userPreferredLanguagesOverride().  It's unused.
- Rename canonicalizedLanguageIdentifier() to canonicalizeLanguageIdentifier().
- Make sure that platformLanguage() and userPreferredLanguages() return language
  codes with '-'.
- Optimize platformLanguage().  It shouldn't create a Vector every time.

BUG=

Review URL: https://codereview.chromium.org/703043002

git-svn-id: svn://svn.chromium.org/blink/trunk@184894 bbb929c8-8fbe-4397-9dbb-9b2b20218538

third_party/WebKit/Source/platform/Language.cpp

@@ -31,39 +31,45 @@
 
 namespace blink {
 
+static String canonicalizeLanguageIdentifier(const String& languageCode)
+{
+    String lowercaseLanguageCode = languageCode.lower();
+    // Platform::defaultLocale() might provide a language code with '_'.
+    lowercaseLanguageCode.replace('_', '-');
+    return lowercaseLanguageCode;
+}
+
 static const AtomicString& platformLanguage()
 {
     DEFINE_STATIC_LOCAL(AtomicString, computedDefaultLanguage, ());
     if (computedDefaultLanguage.isEmpty()) {
-        computedDefaultLanguage = blink::Platform::current()->defaultLocale();
+        computedDefaultLanguage = AtomicString(canonicalizeLanguageIdentifier(Platform::current()->defaultLocale()));
         ASSERT(!computedDefaultLanguage.isEmpty());
     }
     return computedDefaultLanguage;
 }
 
-AtomicString defaultLanguage()
-{
-    Vector<AtomicString> languages = userPreferredLanguages();
-    if (!languages.isEmpty())
-        return languages[0];
-
-    return emptyAtom;
-}
-
 static Vector<AtomicString>& preferredLanguagesOverride()
 {
     DEFINE_STATIC_LOCAL(Vector<AtomicString>, override, ());
     return override;
 }
 
-Vector<AtomicString> userPreferredLanguagesOverride()
+void overrideUserPreferredLanguages(const Vector<AtomicString>& override)
 {
-    return preferredLanguagesOverride();
+    Vector<AtomicString>& canonicalized = preferredLanguagesOverride();
+    canonicalized.resize(0);
+    canonicalized.reserveCapacity(override.size());
+    for (const auto& lang : override)
+        canonicalized.append(canonicalizeLanguageIdentifier(lang));
 }
 
-void overrideUserPreferredLanguages(const Vector<AtomicString>& override)
+AtomicString defaultLanguage()
 {
-    preferredLanguagesOverride() = override;
+    Vector<AtomicString>& override = preferredLanguagesOverride();
+    if (!override.isEmpty())
+        return override[0];
+    return platformLanguage();
 }
 
 Vector<AtomicString> userPreferredLanguages()
@@ -78,16 +84,6 @@ Vector<AtomicString> userPreferredLanguages()
     return languages;
 }
 
-static String canonicalLanguageIdentifier(const String& languageCode)
-{
-    String lowercaseLanguageCode = languageCode.lower();
-
-    if (lowercaseLanguageCode.length() >= 3 && lowercaseLanguageCode[2] == '_')
-        lowercaseLanguageCode.replace(2, 1, "-");
-
-    return lowercaseLanguageCode;
-}
-
 size_t indexOfBestMatchingLanguageInList(const AtomicString& language, const Vector<AtomicString>& languageList)
 {
     AtomicString languageWithoutLocaleMatch;
@@ -97,7 +93,7 @@ size_t indexOfBestMatchingLanguageInList(const AtomicString& language, const Vec
     bool canMatchLanguageOnly = (language.length() == 2 || (language.length() >= 3 && language[2] == '-'));
 
     for (size_t i = 0; i < languageList.size(); ++i) {
-        String canonicalizedLanguageFromList = canonicalLanguageIdentifier(languageList[i]);
+        String canonicalizedLanguageFromList = canonicalizeLanguageIdentifier(languageList[i]);
 
         if (language == canonicalizedLanguageFromList)
             return i;

third_party/WebKit/Source/platform/Language.h

@@ -32,9 +32,13 @@
 
 namespace blink {
 
+// Returns lowercased BCP-47 language tag such as "en-us".  This is the UI
+// locale of the browser application.
 PLATFORM_EXPORT AtomicString defaultLanguage();
+// Returns a list of lowercased BCP-47 language tags.  This never returns
+// multiple values in production.  This is not a value of Accept-Languages
+// header.  See ChromeClient::acceptLanguages.
 PLATFORM_EXPORT Vector<AtomicString> userPreferredLanguages();
-PLATFORM_EXPORT Vector<AtomicString> userPreferredLanguagesOverride();
 PLATFORM_EXPORT void overrideUserPreferredLanguages(const Vector<AtomicString>&);
 PLATFORM_EXPORT size_t indexOfBestMatchingLanguageInList(const AtomicString& language, const Vector<AtomicString>& languageList);
 

third_party/WebKit/Source/web/resources/calendarPicker.js

@@ -49,7 +49,7 @@ var WeekDay = {
 var global = {
     picker: null,
     params: {
-        locale: "en_US",
+        locale: "en-US",
         weekStartDay: WeekDay.Sunday,
         dayLabels: ["S", "M", "T", "W", "T", "F", "S"],
         shortMonthLabels: ["Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sept", "Oct", "Nov", "Dec"],
@@ -75,7 +75,7 @@ function hasInaccuratePointingDevice() {
  * @return {!string} lowercase locale name. e.g. "en-us"
  */
 function getLocale() {
-    return (global.params.locale || "en-us").toLowerCase().replace(/_/g, '-');
+    return global.params.locale || "en-us";
 }
 
 /**