DevTools: carefully cleanup CSS sourcemaps

third_party/WebKit/LayoutTests/inspector/sass/sass-test.js

 var initialize_SassTest = function() {
 
 InspectorTest.preloadModule("sass");
 
 var sassSourceMapFactory = null;
 InspectorTest.sassSourceMapFactory = function()
 {
     if (!sassSourceMapFactory)
         sassSourceMapFactory = new Sass.SASSSourceMapFactory();
     return sassSourceMapFactory;
 }
 
 InspectorTest.parseSCSS = function(url, text)
 {
     return Sass.SASSSupport.parseSCSS(url, text);
 }
 InspectorTest.parseCSS = InspectorTest.parseSCSS;
 
 InspectorTest.loadASTMapping = function(header, callback)
 {
     var sourceMapManager = header.cssModel().sourceMapManager();
     var sourceMap = sourceMapManager.sourceMapForClient(header);
     if (sourceMap)  {
         callback(sourceMap.editable() ? sourceMap : null);
         return;
     }
     sourceMapManager.addEventListener(SDK.SourceMapManager.Events.SourceMapAttached, onAttached);
 
     function onAttached(event) {
-        if (event.data !== header)
+        if (event.data.client !== header)
             return;
         sourceMapManager.removeEventListener(SDK.SourceMapManager.Events.SourceMapAttached, onAttached);
-        var sourceMap = sourceMapManager.sourceMapForClient(header);
+        var sourceMap = event.data.sourceMap;
         callback(sourceMap.editable()? sourceMap : null);
     }
 }
 
 InspectorTest.dumpAST = function(ast)
 {
     var lines = [String.sprintf("=== AST === %s", ast.document.url)];
     for (var i = 0; i < ast.rules.length; ++i) {
         var rule = ast.rules[i];
         lines.push(String.sprintf("rule %d", i));
@@ skipping 261 matching lines @@
     }
     if (!match)
         return null;
     var sourceRange = new TextUtils.SourceRange(match.index, match[0].length);
     var textRange = new TextUtils.Text(source).toTextRange(sourceRange);
     return new TextUtils.SourceEdit("", textRange, newText);
 }
 
 }