Clean up CF To NS Casts and make them slightly safer

base/mac/mac_util.mm

Index: base/mac/mac_util.mm
diff --git a/base/mac/mac_util.mm b/base/mac/mac_util.mm
index 7f3be186daa8c0da82e4b5d58f21b1d70f27d756..14c0ce34f763fbefa2e442e84a034e083964659f 100644
--- a/base/mac/mac_util.mm
+++ b/base/mac/mac_util.mm
@@ -482,3 +482,26 @@ bool WasLaunchedAsHiddenLoginItem() {
 
 }  // namespace mac
 }  // namespace base
+
+std::ostream& operator<<(std::ostream& o, const CFStringRef string) {
+  return o << base::SysCFStringRefToUTF8(string);
+}
+
+std::ostream& operator<<(std::ostream& o, const CFErrorRef err) {
+  base::mac::ScopedCFTypeRef<CFStringRef> desc(CFErrorCopyDescription(err));
+  base::mac::ScopedCFTypeRef<CFDictionaryRef> user_info(
+      CFErrorCopyUserInfo(err));
+  CFStringRef errorDesc = NULL;
+  if (user_info.get()) {
+    errorDesc = reinterpret_cast<CFStringRef>(
+        CFDictionaryGetValue(user_info.get(), kCFErrorDescriptionKey));
+  }
+  o << "Code: " << CFErrorGetCode(err)
+    << " Domain: " << CFErrorGetDomain(err)
+    << " Desc: " << desc.get();
+  if(errorDesc) {
+    o << "(" << errorDesc << ")";
+  }
+  return o;
+}
+