Remove CWV class and move setting User Agent to CWVWebViewConfiguration.

ios/web_view/internal/web_view_browser_state.mm

 // Copyright 2014 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 "ios/web_view/internal/web_view_browser_state.h"
 
 #include <memory>
 
 #include "base/base_paths.h"
 #include "base/files/file_path.h"
@@ skipping 16 matching lines @@
 #endif
 
 namespace {
 const char kPreferencesFilename[] = FILE_PATH_LITERAL("Preferences");
 }
 
 namespace ios_web_view {
 
 WebViewBrowserState::WebViewBrowserState(bool off_the_record)
     : web::BrowserState(), off_the_record_(off_the_record) {
+  // IO access is required to setup the browser state. In Chrome, this is
+  // already allowed during thread startup. However, startup time of
+  // ChromeWebView is not predetermined, so IO access is temporarily allowed.
+  bool wasIOAllowed = base::ThreadRestrictions::SetIOAllowed(true);
+
   CHECK(PathService::Get(base::DIR_APP_DATA, &path_));
 
   request_context_getter_ = new WebViewURLRequestContextGetter(
       GetStatePath(),
       web::WebThread::GetTaskRunnerForThread(web::WebThread::IO),
       web::WebThread::GetTaskRunnerForThread(web::WebThread::FILE),
       web::WebThread::GetTaskRunnerForThread(web::WebThread::CACHE));
 
   // Initialize prefs.
   scoped_refptr<user_prefs::PrefRegistrySyncable> pref_registry =
       new user_prefs::PrefRegistrySyncable;
   RegisterPrefs(pref_registry.get());
   scoped_refptr<base::SequencedTaskRunner> sequenced_task_runner =
       JsonPrefStore::GetTaskRunnerForFile(path_,
                                           web::WebThread::GetBlockingPool());
 
   scoped_refptr<PersistentPrefStore> user_pref_store = new JsonPrefStore(
       path_.Append(kPreferencesFilename), sequenced_task_runner, nullptr);
 
   PrefServiceFactory factory;
   factory.set_user_prefs(user_pref_store);
   prefs_ = factory.Create(pref_registry.get());
+
+  base::ThreadRestrictions::SetIOAllowed(wasIOAllowed);
 }
 
 WebViewBrowserState::~WebViewBrowserState() = default;
 
 PrefService* WebViewBrowserState::GetPrefs() {
   DCHECK(prefs_);
   return prefs_.get();
 }
 
 // static
@@ skipping 19 matching lines @@
   // TODO(crbug.com/679895): Find a good value for the kAcceptLanguages pref.
   // TODO(crbug.com/679895): Pass this value to the network stack somehow, for
   // the HTTP header.
   pref_registry->RegisterStringPref(prefs::kAcceptLanguages,
                                     l10n_util::GetLocaleOverride());
   pref_registry->RegisterBooleanPref(prefs::kEnableTranslate, true);
   translate::TranslatePrefs::RegisterProfilePrefs(pref_registry);
 }
 
 }  // namespace ios_web_view