Unable to copy, evaluate and add variables to watch window

[DonJayamanne]

Environment data

• PTVSD version: Master
• OS and version: N/A
• Python version (& distribution if applicable, e.g. Anaconda): N/A
• Using VS Code or Visual Studio: VSC ('Copy Value' from Variables debugger window not working vscode-python#1398)

Actual behavior

Variables in Variables window cannot be copied.

Expected behavior

Note: I have created Tests for this, we just need to enable a block of code.

Expected behavior

Should be able to copyt

Cause

• The value for evaluateName is not returned for top-level variables
  Source https://github.com/Microsoft/ptvsd/blob/master/ptvsd/wrapper.py#L1742

            eval_name = self._get_variable_evaluate_name(pyd_var, var_name)
            if eval_name:
                var['evaluateName'] = eval_name