DevTools: edit SASS through SourceMaps.

Source/devtools/front_end/workspace/UISourceCode.js

Index: Source/devtools/front_end/workspace/UISourceCode.js
diff --git a/Source/devtools/front_end/workspace/UISourceCode.js b/Source/devtools/front_end/workspace/UISourceCode.js
index 1b374623fc42f589f914df608d9aaf80055a6e1d..ad14992ac681e3fed8182aed0493b15241ecc475 100644
--- a/Source/devtools/front_end/workspace/UISourceCode.js
+++ b/Source/devtools/front_end/workspace/UISourceCode.js
@@ -244,6 +244,19 @@ WebInspector.UISourceCode.prototype = {
     },
 
     /**
+     * @return {!Promise.<?string>}
+     */
+    requestContentPromise: function()
+    {
+        return new Promise(promiseConstructor.bind(this));
+
+        function promiseConstructor(succ, fail)
+        {
+            this.requestContent(succ);
+        }
+    },
+
+    /**
      * @param {function()} callback
      */
     _pushCheckContentUpdatedCallback: function(callback)