Fix integration tests in src/chrome and src/extensions so that we can turn on IO thread checks wi...

chrome/browser/extensions/extension_resource_request_policy_apitest.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 "base/command_line.h"
 #include "base/logging.h"
 #include "build/build_config.h"
 #include "chrome/browser/extensions/extension_apitest.h"
 #include "chrome/browser/ui/browser.h"
 #include "chrome/browser/ui/tabs/tab_strip_model.h"
@@ skipping 59 matching lines @@
   ui_test_utils::NavigateToURL(browser(), non_existent_extension);
   ASSERT_TRUE(content::ExecuteScriptAndExtractString(
       browser()->tab_strip_model()->GetActiveWebContents(),
       "window.domAutomationController.send(document.title)",
       &result));
   EXPECT_EQ(result, "Image failed to load");
 
   // A data URL. Data URLs should always be able to load chrome-extension://
   // resources.
   std::string file_source;
-  ASSERT_TRUE(base::ReadFileToString(
-      test_data_dir_.AppendASCII("extension_resource_request_policy")
-                    .AppendASCII("index.html"), &file_source));
+  {
+    base::ThreadRestrictions::ScopedAllowIO allow_io;
+    ASSERT_TRUE(base::ReadFileToString(
+        test_data_dir_.AppendASCII("extension_resource_request_policy")
+            .AppendASCII("index.html"),
+        &file_source));
+  }
   ui_test_utils::NavigateToURL(browser(),
       GURL(std::string("data:text/html;charset=utf-8,") + file_source));
   ASSERT_TRUE(content::ExecuteScriptAndExtractString(
       browser()->tab_strip_model()->GetActiveWebContents(),
       "window.domAutomationController.send(document.title)",
       &result));
   EXPECT_EQ(result, "Loaded");
 
   // A different extension. Legacy (manifest_version 1) extensions should always
   // be able to load each other's resources.
@@ skipping 253 matching lines @@
   // The iframe should not load |private_page|, which is not web-accessible.
   //
   // TODO(alexmos): The failure mode differs on whether or not
   // --isolate-extensions is used: if it is on, the request is canceled and we
   // stay on public.html (see https://crbug.com/656752), and if it's off, the
   // request is blocked in ExtensionNavigationThrottle, which loads an error
   // page into the iframe.  This check handles both cases, but we should make
   // the check stricter once --isolate-extensions is on by default.
   EXPECT_NE("Private", content);
 }