code: function _getProvidersForLanguageId(languageId) {
          var providers = hintProviders[languageId] || hintProviders.all;
  
          // Exclude providers that are explicitly disabled in the preferences.
          // All code hint providers that do not have their constructor
          // names listed in the preferences are enabled by default.
          return providers.filter(function (provider) {
              var prefKey = "codehint." + provider.provider.constructor.name;
              return PreferencesManager.get(prefKey) !== false;
          });
      }
docs: Return the array of hint providers for the given language id.
  This gets called (potentially) on every keypress. So, it should be fast.
  
  @param {!string} languageId
  @return {?Array.<{provider: Object, priority: number}>}