[ObjC ARC] Converts parts of ios/web/webstate to ARC.

ios/web/web_state/ui/web_view_js_utils.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/web_state/ui/web_view_js_utils.h"
 
 #include <CoreFoundation/CoreFoundation.h>
 #import <WebKit/WebKit.h>
 
 #include "base/logging.h"
 #include "base/mac/foundation_util.h"
 #include "base/mac/scoped_nsobject.h"
 #include "base/memory/ptr_util.h"
 #include "base/strings/sys_string_conversions.h"
 #include "base/values.h"
 
+#if !defined(__has_feature) || !__has_feature(objc_arc)
+#error "This file requires ARC support."
+#endif
+
 namespace {
 
 // Converts result of WKWebView script evaluation to base::Value, parsing
 // |wk_result| up to a depth of |max_depth|.
 std::unique_ptr<base::Value> ValueResultFromWKResult(id wk_result,
                                                      int max_depth) {
   if (!wk_result)
     return nullptr;
 
   std::unique_ptr<base::Value> result;
 
   if (max_depth < 0) {
     DLOG(WARNING) << "JS maximum recursion depth exceeded.";
     return result;
   }
 
-  CFTypeID result_type = CFGetTypeID(wk_result);
+  CFTypeID result_type = CFGetTypeID((__bridge CFTypeRef)wk_result);
   if (result_type == CFStringGetTypeID()) {
     result.reset(new base::StringValue(base::SysNSStringToUTF16(wk_result)));
     DCHECK(result->IsType(base::Value::TYPE_STRING));
   } else if (result_type == CFNumberGetTypeID()) {
     result.reset(new base::FundamentalValue([wk_result doubleValue]));
     DCHECK(result->IsType(base::Value::TYPE_DOUBLE));
   } else if (result_type == CFBooleanGetTypeID()) {
     result.reset(
         new base::FundamentalValue(static_cast<bool>([wk_result boolValue])));
     DCHECK(result->IsType(base::Value::TYPE_BOOLEAN));
@@ skipping 54 matching lines @@
                 userInfo:@{NSLocalizedDescriptionKey : error_message}]);
       completion_handler(nil, error);
     });
     return;
   }
 
   [web_view evaluateJavaScript:script completionHandler:completion_handler];
 }
 
 }  // namespace web