DevTools: remove extra indirections from how extension API is built

third_party/WebKit/LayoutTests/http/tests/inspector/extensions-test.js

 function extensionFunctions()
 {
     var functions = "";
 
     for (symbol in window) {
         if (/^extension_/.exec(symbol) && typeof window[symbol] === "function")
             functions += window[symbol].toString();
     }
     return functions;
 }
 
 var initialize_ExtensionsTest = function()
 {
+WebInspector.extensionServer._registerHandler("evaluateForTestInFrontEnd", onEvaluate);
 
-WebInspector.extensionServer._overridePlatformExtensionAPIForTest = function(extensionInfo, inspectedTabId, themeName)
+WebInspector.extensionServer._extensionAPITestHook = function(extensionServerClient, coreAPI)
 {
-    WebInspector.extensionServer._registerHandler("evaluateForTestInFrontEnd", onEvaluate);
-
-    function platformExtensionAPI(coreAPI)
-    {
-        window.webInspector = coreAPI;
-        window._extensionServerForTests = extensionServer;
-        coreAPI.panels.themeName = "themeNameForTest";
-    }
-    return platformExtensionAPI.toString();
+    window.webInspector = coreAPI;
+    window._extensionServerForTests = extensionServerClient;
+    coreAPI.panels.themeName = "themeNameForTest";
 }
 
 InspectorTest._replyToExtension = function(requestId, port)
 {
     WebInspector.extensionServer._dispatchCallback(requestId, port);
 }
 
 function onEvaluate(message, port)
 {
     function reply(param)
@@ skipping 35 matching lines @@
 
 function extension_showPanel(panelId, callback)
 {
     evaluateOnFrontend("InspectorTest.showPanel(unescape('" + escape(panelId) + "')).then(function() { reply(); });", callback);
 }
 
 var test = function()
 {
     InspectorTest.runExtensionTests();
 }