Make PrefixedPreferencesSystem context aware.

Author: busykai

src/document/DocumentManager.js

@@ -695,18 +695,21 @@ define(function (require, exports, module) {
             oldDoc.off("languageChanged.DocumentManager");
         }
 
-        if (newDoc !== oldDoc) {
-            // Dispatch deprecated event with doc args (not File args as the new event uses)
-            exports.trigger("currentDocumentChange", newDoc, oldDoc);
-        }
-
         if (newDoc) {
+            PreferencesManager._setCurrentLanguage(newDoc.getLanguage().getId());
             newDoc.on("languageChanged.DocumentManager", function (e, oldLang, newLang) {
                 PreferencesManager._setCurrentLanguage(newLang.getId());
                 exports.trigger("currentDocumentLanguageChanged", [oldLang, newLang]);
             });
+        } else {
+            PreferencesManager._setCurrentLanguage(undefined);
         }
 
+        if (newDoc !== oldDoc) {
+            // Dispatch deprecated event with doc args (not File args as the new event uses)
+            exports.trigger("currentDocumentChange", newDoc, oldDoc);
+        }
+
     });
 
     // Deprecated APIs   

src/preferences/PreferencesBase.js

@@ -1062,7 +1062,8 @@ define(function (require, exports, module) {
          * @param {Object=} context Optional context object to change the preference lookup
          */
         get: function (id, context) {
-            return this.base.get(this.prefix + id, context);
+            context = context || {};
+            return this.base.get(this.prefix + id, this.base._getContext(context));
         },
 
         /**

src/preferences/PreferencesManager.js

@@ -422,9 +422,13 @@ define(function (require, exports, module) {
         var ctx = {};
         if (filename) {
             ctx.path = filename;
+        } else {
+            ctx.path = currentFilename;
         }
         if (languageId) {
             ctx.language = languageId;
+        } else {
+            ctx.language = currentLanguageId;
         }
         ctx.scopeOrder = _includeProjectScope(ctx.path) ?
                         scopeOrderWithProject :