0025987: Is impossible to edit a record in parameter tab in grid view

This issue has been caused by the smartclient upgrade. The problem is the following:
- Smartclient does not support properly having fields named 'length'. If the getField(fieldName) function is executed on a grid with fieldName = 'length', it does not return the field named length, but the actual length of the field array. This worked this way also in the previous smartclient version.
- The behavior of the getField function is now a problem because of a change in the validateRowValues function:

Before the upgrade:
...
        if (!shouldValidateCell) {
            var field = this.getField(fieldName),
                dataPath = field ? field.dataPath : null,
                undef;
            if (dataPath != null) {
                newValue = isc.Canvas._getFieldValue(this._trimDataPath(dataPath), null, newValues,
                                                                this, true);
                oldValue = isc.Canvas._getFieldValue(this._trimDataPath(dataPath), null, oldValues,
                                                                this, true);
                shouldValidateCell = (newValue !== undef || oldValue === undef);
            }
        } else {
            newValue = newValues[fieldName];
            oldValue = oldValues[fieldName];
        }
...

shouldValidateCell is true for the 'length' field, so the values were taken from newValues and oldValues, the faulty getField function was not called.

After the upgrade:
...
        var field = this.getField(fieldName),
            dataPath = field ? field.dataPath : null,
            undef;
        if (dataPath != null) {
            dataPath = this._trimDataPath(dataPath);
        } else {
            dataPath = field.name;
        }

        newValue = isc.Canvas._getFieldValue(dataPath, field, newValues,
                                                        this, true);
        oldValue = isc.Canvas._getFieldValue(dataPath, field, oldValues,
                                                            this, true);
...

Now the getField function is always called. Failing to return a proper field for the 'length' fieldName, newValue and oldValue remain null, and the field does not pass the validation to check that its value is has been set (the field is set as mandatory).