Place <webview> tag behind a flag.

chrome/browser/extensions/web_view_browsertest.cc

 // 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.
 
 #include "chrome/browser/automation/automation_util.h"
 #include "chrome/browser/extensions/platform_app_browsertest_util.h"
 #include "chrome/browser/ui/browser_tabstrip.h"
+#include "chrome/common/chrome_switches.h"
 #include "chrome/test/base/ui_test_utils.h"
 #include "chrome/test/base/test_launcher_utils.h"
 #include "content/public/browser/notification_service.h"
 #include "content/public/browser/render_process_host.h"
 #include "content/public/test/browser_test_utils.h"
 #include "ui/compositor/compositor_setup.h"
 #include "ui/gl/gl_switches.h"
 
 class WebViewTest : public extensions::PlatformAppBrowserTest {
  protected:
   virtual void SetUpCommandLine(CommandLine* command_line) {
     extensions::PlatformAppBrowserTest::SetUpCommandLine(command_line);
+    // Enable <webview> for running test.
+    command_line->AppendSwitch(switches::kEnableWebView);
 #if !defined(OS_MACOSX)
     CHECK(test_launcher_utils::OverrideGLImplementation(
           command_line, gfx::kGLImplementationOSMesaName)) <<
           "kUseGL must not be set by test framework code!";
 #endif
     ui::DisableTestCompositor();
   }
 };
 
 IN_PROC_BROWSER_TEST_F(WebViewTest, Shim) {
@@ skipping 75 matching lines @@
   automation_util::GetCookies(GURL("http://localhost"),
                               source1->GetWebContents(),
                               &cookie_size, &cookie_value);
   EXPECT_EQ("guest1=true", cookie_value);
 
   automation_util::GetCookies(GURL("http://localhost"),
                               source2->GetWebContents(),
                               &cookie_size, &cookie_value);
   EXPECT_EQ("guest2=true", cookie_value);
 }