Shift cookie system callbacks to OnceCallback to impedance match mojo.

ios/net/cookies/cookie_store_ios_unittest.mm

 // Copyright 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 "ios/net/cookies/cookie_store_ios.h"
 
 #import <Foundation/Foundation.h>
 
 #include <memory>
 
@@ skipping 78 matching lines @@
         store_(base::MakeUnique<net::CookieStoreIOS>(
             [NSHTTPCookieStorage sharedHTTPCookieStorage])) {
     cookie_changed_callback_ = store_->AddCallbackForCookie(
         kTestCookieURL, "abc",
         base::Bind(&RecordCookieChanges, &cookies_changed_, &cookies_removed_));
   }
 
   ~CookieStoreIOSTest() override {}
 
   // Gets the cookies. |callback| will be called on completion.
-  void GetCookies(const net::CookieStore::GetCookiesCallback& callback) {
+  void GetCookies(net::CookieStore::GetCookiesCallback callback) {
     net::CookieOptions options;
     options.set_include_httponly();
-    store_->GetCookiesWithOptionsAsync(kTestCookieURL, options, callback);
+    store_->GetCookiesWithOptionsAsync(kTestCookieURL, options,
+                                       std::move(callback));
   }
 
   // Sets a cookie.
   void SetCookie(const std::string& cookie_line) {
     net::SetCookie(cookie_line, kTestCookieURL, store_.get());
   }
 
   void SetSystemCookie(const GURL& url,
                        const std::string& name,
                        const std::string& value) {
@@ skipping 291 matching lines @@
   SetSystemCookie(kTestCookieURL, "abc", "ghi");
   EXPECT_EQ(2U, cookies.size());
   // this deletes the callback
   handle.reset();
   SetSystemCookie(kTestCookieURL, "abc", "jkl");
   EXPECT_EQ(2U, cookies.size());
   DeleteSystemCookie(kTestCookieURL, "abc");
 }
 
 }  // namespace net