Shift cookie system callbacks to OnceCallback to impedance match mojo.

ios/net/cookies/cookie_store_ios_persistent_unittest.mm

 // Copyright 2017 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/net/cookies/cookie_store_ios_persistent.h"
 
 #import <Foundation/Foundation.h>
 
 #include <memory>
 
@@ skipping 45 matching lines @@
             base::MakeUnique<net::CookieStoreIOSPersistent>(backend_.get())) {
     cookie_changed_callback_ = store_->AddCallbackForCookie(
         kTestCookieURL, "abc",
         base::Bind(&net::RecordCookieChanges, &cookies_changed_,
                    &cookies_removed_));
   }
 
   ~CookieStoreIOSPersistentTest() 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());
   }
 
  private:
   const GURL kTestCookieURL;
 
@@ skipping 32 matching lines @@
   EXPECT_TRUE(cookies_removed_[1]);
   EXPECT_EQ("abc", cookies_changed_[2].Name());
   EXPECT_EQ("ghi", cookies_changed_[2].Value());
   EXPECT_FALSE(cookies_removed_[2]);
 }
 
 // Tests that cookies can be read before the backend is loaded.
 TEST_F(CookieStoreIOSPersistentTest, NotSynchronized) {
   // Start fetching the cookie.
   GetCookieCallback callback;
-  GetCookies(base::Bind(&GetCookieCallback::Run, base::Unretained(&callback)));
+  GetCookies(
+      base::BindOnce(&GetCookieCallback::Run, base::Unretained(&callback)));
   // Backend loading completes.
   backend_->RunLoadedCallback();
   EXPECT_TRUE(callback.did_run());
   EXPECT_EQ("a=b", callback.cookie_line());
 }
 
 }  // namespace net