Revert of Revert "Revert of Reland: Switch WindowedNotificationObserver to use base::RunLoop.

chrome/browser/ui/webui/net_internals/net_internals_ui_browsertest.cc

Index: chrome/browser/ui/webui/net_internals/net_internals_ui_browsertest.cc
diff --git a/chrome/browser/ui/webui/net_internals/net_internals_ui_browsertest.cc b/chrome/browser/ui/webui/net_internals/net_internals_ui_browsertest.cc
index d6abca1b06ea2d80a889783649c6488255823be5..c11dfe2a9bca0f7eb8f7538bafa711dc211c2baa 100644
--- a/chrome/browser/ui/webui/net_internals/net_internals_ui_browsertest.cc
+++ b/chrome/browser/ui/webui/net_internals/net_internals_ui_browsertest.cc
@@ -104,12 +104,6 @@
  private:
   void RegisterMessages() override;
 
-  void RegisterMessage(const std::string& message,
-                       const content::WebUI::MessageCallback& handler);
-
-  void HandleMessage(const content::WebUI::MessageCallback& handler,
-                     const base::ListValue* data);
-
   // Runs NetInternalsTest.callback with the given value.
   void RunJavascriptCallback(base::Value* value);
 
@@ -168,59 +162,39 @@
 }
 
 void NetInternalsTest::MessageHandler::RegisterMessages() {
-  RegisterMessage(
-      "getTestServerURL",
+  web_ui()->RegisterMessageCallback("getTestServerURL",
       base::Bind(&NetInternalsTest::MessageHandler::GetTestServerURL,
                  base::Unretained(this)));
-  RegisterMessage("addCacheEntry",
-                  base::Bind(&NetInternalsTest::MessageHandler::AddCacheEntry,
-                             base::Unretained(this)));
-  RegisterMessage("changeNetwork",
-                  base::Bind(&NetInternalsTest::MessageHandler::ChangeNetwork,
-                             base::Unretained(this)));
-  RegisterMessage("loadPage",
-                  base::Bind(&NetInternalsTest::MessageHandler::LoadPage,
-                             base::Unretained(this)));
-  RegisterMessage("prerenderPage",
-                  base::Bind(&NetInternalsTest::MessageHandler::PrerenderPage,
-                             base::Unretained(this)));
-  RegisterMessage(
-      "navigateToPrerender",
+  web_ui()->RegisterMessageCallback("addCacheEntry",
+      base::Bind(&NetInternalsTest::MessageHandler::AddCacheEntry,
+                 base::Unretained(this)));
+  web_ui()->RegisterMessageCallback(
+      "changeNetwork",
+      base::Bind(&NetInternalsTest::MessageHandler::ChangeNetwork,
+                 base::Unretained(this)));
+  web_ui()->RegisterMessageCallback("loadPage",
+      base::Bind(&NetInternalsTest::MessageHandler::LoadPage,
+                  base::Unretained(this)));
+  web_ui()->RegisterMessageCallback("prerenderPage",
+      base::Bind(&NetInternalsTest::MessageHandler::PrerenderPage,
+                  base::Unretained(this)));
+  web_ui()->RegisterMessageCallback("navigateToPrerender",
       base::Bind(&NetInternalsTest::MessageHandler::NavigateToPrerender,
                  base::Unretained(this)));
-  RegisterMessage(
-      "createIncognitoBrowser",
+  web_ui()->RegisterMessageCallback("createIncognitoBrowser",
       base::Bind(&NetInternalsTest::MessageHandler::CreateIncognitoBrowser,
                  base::Unretained(this)));
-  RegisterMessage(
-      "closeIncognitoBrowser",
+  web_ui()->RegisterMessageCallback("closeIncognitoBrowser",
       base::Bind(&NetInternalsTest::MessageHandler::CloseIncognitoBrowser,
                  base::Unretained(this)));
-  RegisterMessage(
-      "getNetLogFileContents",
-      base::Bind(&NetInternalsTest::MessageHandler::GetNetLogFileContents,
-                 base::Unretained(this)));
-  RegisterMessage(
-      "enableDataReductionProxy",
-      base::Bind(&NetInternalsTest::MessageHandler::EnableDataReductionProxy,
-                 base::Unretained(this)));
-}
-
-void NetInternalsTest::MessageHandler::RegisterMessage(
-    const std::string& message,
-    const content::WebUI::MessageCallback& handler) {
-  web_ui()->RegisterMessageCallback(
-      message, base::Bind(&NetInternalsTest::MessageHandler::HandleMessage,
-                          base::Unretained(this), handler));
-}
-
-void NetInternalsTest::MessageHandler::HandleMessage(
-    const content::WebUI::MessageCallback& handler,
-    const base::ListValue* data) {
-  // The handler might run a nested loop to wait for something.
-  base::MessageLoop::ScopedNestableTaskAllower nestable_task_allower(
-      base::MessageLoop::current());
-  handler.Run(data);
+  web_ui()->RegisterMessageCallback("getNetLogFileContents",
+      base::Bind(
+          &NetInternalsTest::MessageHandler::GetNetLogFileContents,
+          base::Unretained(this)));
+  web_ui()->RegisterMessageCallback("enableDataReductionProxy",
+      base::Bind(
+          &NetInternalsTest::MessageHandler::EnableDataReductionProxy,
+          base::Unretained(this)));
 }
 
 void NetInternalsTest::MessageHandler::RunJavascriptCallback(