Go to symbol in workspace fails

[DonJayamanne]

• Language Server version 0.1.63
• Open PTVSD repo
• Open the file src/ptvsd/_remote.py
• From the command palette select Go to symbol in workspace
• Kaboom:

Starting Microsoft Python language server.
Microsoft Python Language Server version 0.1.63.0
Initializing for /Users/donjayamanne/.local/share/virtualenvs/Algorithm-Y3rXutxy/bin/python
[Error - 3:26:01 PM] Request workspace/symbol failed.
  Message: Object reference not set to an instance of an object.
  Code: -32000 
   at Microsoft.Python.LanguageServer.Implementation.Server.<>c__DisplayClass133_0.<GetModuleVariables>b__4(ILocationInfo l)
   at System.Linq.Enumerable.Any[TSource](IEnumerable`1 source, Func`2 predicate)
   at System.Linq.Enumerable.Any[TSource](IEnumerable`1 source, Func`2 predicate)
   at Microsoft.Python.LanguageServer.Implementation.Server.<>c__DisplayClass133_0.<GetModuleVariables>b__2(IMemberResult m)
   at System.Linq.Enumerable.WhereEnumerableIterator`1.MoveNext()
   at System.Linq.Enumerable.EnumerablePartition`1.ToList()
   at System.Linq.Enumerable.ToList[TSource](IEnumerable`1 source)
   at Microsoft.Python.LanguageServer.Implementation.Server.GetModuleVariablesAsync(ProjectEntry entry, GetMemberOptions opts, String prefix, Int32 timeout, CancellationToken token)
   at Microsoft.Python.LanguageServer.Implementation.Server.WorkspaceSymbols(WorkspaceSymbolParams params, CancellationToken cancellationToken)
   at Microsoft.Python.LanguageServer.Implementation.LanguageServer.WorkspaceSymbols(JToken token, CancellationToken cancellationToken)

[jakebailey]

Duplicate of #419.

[jakebailey]

Err, I mean #378.