Upstream most of ios/web/net

ios/web/ui_web_view_util.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.
+
+#import "ios/web/ui_web_view_util.h"
+
+#include "base/logging.h"
+#include "base/mac/scoped_nsobject.h"
+#include "base/strings/sys_string_conversions.h"
+#include "ios/web/net/request_group_util.h"
+#include "ios/web/public/web_client.h"
+
+namespace {
+// Returns true if given Request Group ID string contains only decimal digits.
+BOOL IsValidRequestGroupID(NSString* request_group_id) {
+  return [[NSCharacterSet decimalDigitCharacterSet] isSupersetOfSet:
+      [NSCharacterSet characterSetWithCharactersInString:request_group_id]];
+}
+}  // namespace
+
+namespace web {
+
+void BuildAndRegisterUserAgentForUIWebView(NSString* request_group_id,
+                                           BOOL use_desktop_user_agent) {
+  DCHECK(!request_group_id || IsValidRequestGroupID(request_group_id));
+  DCHECK(web::GetWebClient());
+  std::string baseUserAgent = web::GetWebClient()->GetUserAgent(
+      use_desktop_user_agent);
+  web::RegisterUserAgentForUIWebView(
+      web::AddRequestGroupIDToUserAgent(base::SysUTF8ToNSString(baseUserAgent),
+                                        request_group_id));
+}
+
+void RegisterUserAgentForUIWebView(NSString* user_agent) {
+  [[NSUserDefaults standardUserDefaults] registerDefaults:@{
+    @"UserAgent" : user_agent
+  }];
+}
+
+}  // namespace web