Test Explorer buttons don't show

[rschiefer]

Environment data

• VS Code version: 1.36.1
• Extension version (available under the Extensions sidebar): 2019.8.29288
• OS and version: Windows_NT x64 10.0.18362
• Python version (& distribution if applicable, e.g. Anaconda): 2/3

Expected behaviour

Test explorer buttons/icons show normally for python unittest tests.

Actual behaviour

When VSCode is started from folder in WSL ("code .") the buttons in the test explorer dont' show.

Steps to reproduce:

1. Open VSCode from WSL folder ("code .")
2. Go to Test Explorer and see the buttons/icons don't show
3. Close folder in VSCode then reopen to see buttons/icons

Output from Console under the Developer Tools panel (toggle Developer Tools on under Help; turn on source maps to make any tracebacks be useful by running Enable source map support for extension debugging)

Info Python Extension: 2019-08-06 21:46:16: autoSelectInterpreter, Class name = f, completed in 657ms, Arg 1: undefined, Return Value: undefined
open-change.svg:1 Failed to load resource: net::ERR_NOT_IMPLEMENTED
repl.svg:1 Failed to load resource: net::ERR_NOT_IMPLEMENTED
refresh.svg:1 Failed to load resource: net::ERR_NOT_IMPLEMENTED
debug.svg:1 Failed to load resource: net::ERR_NOT_IMPLEMENTED
run-tests.svg:1 Failed to load resource: net::ERR_NOT_IMPLEMENTED
console.ts:134 [Extension Host] Info Python Extension: 2019-08-06 21:46:23: Cached data exists ActivatedEnvironmentVariables, /mnt/c/Users/rschiefer/suture/suturesign-providerdata/Suture.DataPipeline.Provider

[DonJayamanne]

Closing in favor of upstream issue.