Run ContentMain in a browser_test's browser process. This removes duplication of code in the browse…

chrome/browser/ui/cocoa/extensions/extension_install_dialog_controller_browsertest.mm

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #import "chrome/browser/ui/cocoa/extensions/extension_install_dialog_controller.h"
 
 #include "chrome/browser/ui/browser.h"
 #include "chrome/browser/ui/cocoa/constrained_window/constrained_window_sheet_controller.h"
 #import "chrome/browser/ui/cocoa/extensions/extension_install_prompt_test_utils.h"
 #import "chrome/browser/ui/cocoa/extensions/extension_install_view_controller.h"
 #include "chrome/browser/ui/tabs/tab_strip_model.h"
 #include "chrome/test/base/in_process_browser_test.h"
 #include "extensions/common/extension.h"
 
 using extensions::Extension;
 
 class ExtensionInstallDialogControllerTest : public InProcessBrowserTest {
 public:
-  ExtensionInstallDialogControllerTest() {
+  ExtensionInstallDialogControllerTest() {}
+
+  virtual void SetUpOnMainThread() OVERRIDE {
     extension_ = chrome::LoadInstallPromptExtension();
   }
 
  protected:
   scoped_refptr<Extension> extension_;
 };
 
 IN_PROC_BROWSER_TEST_F(ExtensionInstallDialogControllerTest, BasicTest) {
   content::WebContents* tab = browser()->tab_strip_model()->GetWebContentsAt(0);
   ExtensionInstallPrompt::ShowParams show_params(tab);
@@ skipping 35 matching lines @@
   base::scoped_nsobject<NSWindow> window(
       [[[controller->view_controller() view] window] retain]);
   EXPECT_TRUE([window isVisible]);
 
   // Press cancel to close the window
   [[controller->view_controller() cancelButton] performClick:nil];
 
   // Wait for the window to finish closing.
   EXPECT_FALSE([window isVisible]);
 }