Revert of Stop doing unnecessary UTF-8 to UTF-16 conversions in JSONWriter.

jingle/notifier/listener/notification_defines.cc

Index: jingle/notifier/listener/notification_defines.cc
diff --git a/jingle/notifier/listener/notification_defines.cc b/jingle/notifier/listener/notification_defines.cc
index f7c8f8fd3ad5dd8fe90af742720f7a6c137efb87..f4f3e408a5b795f8fa80826cdae43158d9479706 100644
--- a/jingle/notifier/listener/notification_defines.cc
+++ b/jingle/notifier/listener/notification_defines.cc
@@ -65,12 +65,10 @@
 }
 
 std::string Notification::ToString() const {
-  // |channel| or |data| could hold binary data, so convert all non-ASCII
-  // characters to escape sequences.
-  const std::string& printable_channel =
-      base::EscapeBytesAsInvalidJSONString(channel, true /* put_in_quotes */);
-  const std::string& printable_data =
-      base::EscapeBytesAsInvalidJSONString(data, true /* put_in_quotes */);
+  // |channel| or |data| could hold binary data, so use GetDoubleQuotedJson()
+  // to escape them.
+  const std::string& printable_channel = base::GetDoubleQuotedJson(channel);
+  const std::string& printable_data = base::GetDoubleQuotedJson(data);
   return
       "{ channel: " + printable_channel + ", data: " + printable_data + " }";
 }