[ObjC ARC] Converts ios/chrome/browser/passwords:unit_tests to ARC.

ios/chrome/browser/passwords/credential_manager_js_unittest.mm

 // Copyright 2015 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 <memory>
 
 #include "base/mac/foundation_util.h"
-#import "base/mac/scoped_nsobject.h"
 #include "base/strings/utf_string_conversions.h"
 #include "base/values.h"
 #import "ios/chrome/browser/passwords/js_credential_manager.h"
 #include "ios/web/public/web_state/credential.h"
 #import "ios/web/public/web_state/js/crw_js_injection_receiver.h"
 #import "ios/web/public/web_state/web_state.h"
 #include "ios/web/public/web_state/web_state_observer.h"
 #import "ios/web/public/test/web_test_with_web_state.h"
 #include "testing/gmock/include/gmock/gmock.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "testing/gtest_mac.h"
 #include "url/gurl.h"
 
+#if !defined(__has_feature) || !__has_feature(objc_arc)
+#error "This file requires ARC support."
+#endif
+
 namespace {
 
 using ::testing::_;
 
 // Matcher to match web::Credential.
 MATCHER_P(IsEqualTo, value, "") {
   return arg.type == value.type && arg.id == value.id &&
          arg.name == value.name && arg.avatar_url == value.avatar_url &&
          arg.password == value.password &&
          arg.federation_origin.Serialize() ==
@@ skipping 20 matching lines @@
   DISALLOW_COPY_AND_ASSIGN(MockWebStateObserver);
 };
 
 // Unit tests for the Credential Manager JavaScript and associated plumbing.
 class CredentialManagerJsTest : public web::WebTestWithWebState {
  public:
   CredentialManagerJsTest() {}
 
   void SetUp() override {
     web::WebTestWithWebState::SetUp();
-    js_credential_manager_.reset(base::mac::ObjCCastStrict<JSCredentialManager>(
-        [[web_state()->GetJSInjectionReceiver()
-            instanceOfClass:[JSCredentialManager class]] retain]));
+    js_credential_manager_ = base::mac::ObjCCastStrict<JSCredentialManager>(
+        [web_state()->GetJSInjectionReceiver()
+            instanceOfClass:[JSCredentialManager class]]);
     observer_.reset(new MockWebStateObserver(web_state()));
   }
 
   // Sets up a web page and injects the JSCredentialManager. Must be called
   // before any interaction with the page.
   void Inject() {
     LoadHtml(@"");
     [js_credential_manager_ inject];
   }
 
@@ skipping 173 matching lines @@
                             NSString* message,
                             NSString* promise) {
     PrepareResolverAndRejecter(promise);
     RejectPromise(request_id, error, message);
     CheckRejected(error, message);
     CheckNeverResolved();
   }
 
  private:
   // Manager for injected credential manager JavaScript.
-  base::scoped_nsobject<JSCredentialManager> js_credential_manager_;
+  JSCredentialManager* js_credential_manager_;
 
   // Mock observer for testing.
   std::unique_ptr<MockWebStateObserver> observer_;
 
   DISALLOW_COPY_AND_ASSIGN(CredentialManagerJsTest);
 };
 
 // Tests that navigator.credentials calls use distinct request identifiers.
 TEST_F(CredentialManagerJsTest, RequestIdentifiersDiffer) {
   Inject();
@@ skipping 227 matching lines @@
 TEST_F(CredentialManagerJsTest,
        RejectPromiseWithSecurityError_notifySignedOut) {
   Inject();
   const int request_id = 0;
   EXPECT_CALL(observer(), SignedOut(request_id, _));
   TestPromiseRejection(request_id, @"SecurityError", @"foo",
                        @"navigator.credentials.notifySignedOut()");
 }
 
 }  // namespace