i#943 non-ascii: fix full_path of exe
i#943 non-ascii: fix full_path of exe

Fixes inject_shared.'s wchar_to_char() to use utf16_to_utf8_size() rather
than an incorrect scale.  This avoids truncating non-ascii names in module
data.

Review-URL: https://codereview.appspot.com/301700043

AmesianX/dynamorio,AmesianX/dynamorio,AmesianX/dynamorio,AmesianX/dynamorio,AmesianX/dynamorio