If user profile doesn't contain language setting, default to his Google account settings.

chrome/browser/profiles/profile.h

Index: chrome/browser/profiles/profile.h
diff --git a/chrome/browser/profiles/profile.h b/chrome/browser/profiles/profile.h
index 3af9eeb3c6176af068cef908cb168cc99dd79ed1..27fc5e5a357d18aa3fd65da0b5933840a5d4dd75 100644
--- a/chrome/browser/profiles/profile.h
+++ b/chrome/browser/profiles/profile.h
@@ -293,6 +293,9 @@ class Profile : public content::BrowserContext {
   virtual void ChangeAppLocale(
       const std::string& locale, AppLocaleChangedVia via) = 0;
 
+  // Mark profile creation complete (i.e. initial load complete).
+  virtual void MarkCreated() = 0;
+
   // Called after login.
   virtual void OnLogin() = 0;
 
@@ -301,6 +304,12 @@ class Profile : public content::BrowserContext {
 
   // Initializes Chrome OS's preferences.
   virtual void InitChromeOSPreferences() = 0;
+
+  // Select "best match" locale.
+  virtual void RespectLocalePreference() = 0;
+
+  // Sets locale to G+ if use preferences are not loaded.
+  virtual void SetGPlusProfileLocale(const std::string& gplus_locale) = 0;
 #endif  // defined(OS_CHROMEOS)
 
   // Returns the helper object that provides the proxy configuration service