[ObjC ARC] Converts ios/web:ios_web_webui_unittests to ARC.

ios/web/webui/crw_web_ui_page_builder_unittest.mm

Index: ios/web/webui/crw_web_ui_page_builder_unittest.mm
diff --git a/ios/web/webui/crw_web_ui_page_builder_unittest.mm b/ios/web/webui/crw_web_ui_page_builder_unittest.mm
index 67c29326fea11872c9eeebacfe69573a3e62f3f5..0e5423785479693abdbbb3f93a9e29c621286b14 100644
--- a/ios/web/webui/crw_web_ui_page_builder_unittest.mm
+++ b/ios/web/webui/crw_web_ui_page_builder_unittest.mm
@@ -7,13 +7,16 @@
 #import <Foundation/Foundation.h>
 
 #include "base/logging.h"
-#import "base/mac/scoped_nsobject.h"
 #include "base/strings/sys_string_conversions.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #import "testing/gtest_mac.h"
 #include "testing/platform_test.h"
 #include "url/gurl.h"
 
+#if !defined(__has_feature) || !__has_feature(objc_arc)
+#error "This file requires ARC support."
+#endif
+
 namespace {
 
 // HTML page template.
@@ -169,14 +172,14 @@ class CRWWebUIPageBuilderTest : public PlatformTest {
  protected:
   void SetUp() override {
     PlatformTest::SetUp();
-    delegate_.reset([[MockPageBuilderDelegate alloc] init]);
-    web_ui_page_builder_.reset(
-        [[MockCRWWebUIPageBuilder alloc] initWithDelegate:delegate_]);
+    delegate_ = [[MockPageBuilderDelegate alloc] init];
+    web_ui_page_builder_ =
+        [[MockCRWWebUIPageBuilder alloc] initWithDelegate:delegate_];
   }
   // CRWWebUIPageBuilder for testing.
-  base::scoped_nsobject<MockCRWWebUIPageBuilder> web_ui_page_builder_;
+  MockCRWWebUIPageBuilder* web_ui_page_builder_;
   // Delegate for test CRWWebUIPageBuilder.
-  base::scoped_nsobject<MockPageBuilderDelegate> delegate_;
+  MockPageBuilderDelegate* delegate_;
 };
 
 // Tests that a page without imports is passed to completion handler unchanged.