Encoding numbers as json is buggy.

[xxgreg]

Typeconverter.dart Line: 163

Change to:

 if (value is num) {
      ...
      var n = value.toString();
      return "'$n'";
 }

Also note doc comment is wrong.

//FIXME can probably simplify this, as in postgresql json type must take
// map or array at top level, not string or number. (I think???)
String encodeValueToJson(value, {getConnectionName()}) {
if (value == null)
return "'null'";

if (value is Map || value is List)
  return encodeString(JSON.encode(value));

if (value is String)
  return encodeString('"$value"');

if (value is num) {
  // These are not valid JSON numbers, so encode them as strings.
  // TODO consider throwing an error instead.
  if (value.isNaN) return '"nan"';
  if (value == double.INFINITY) return '"infinity"';
  if (value == double.NEGATIVE_INFINITY) return '"-infinity"';
  return value.toString();
}

try {
  var map = value.toJson();
  return encodeString(JSON.encode(value));
} catch (e) {
  throw _error('Could not convert object to JSON. '
      'No toJson() method was implemented on the object.', getConnectionName);
}

}