windows gks_qt fix

[t-bltg]

Fix #475.

@BioTurboNick, if you could confirm, thanks a lot.

I really don't know how to write a test for this, so it does not reproduce ...
We really need low-level gr debugging tools (JuliaPlots/Plots.jl#4375 (comment)).

[codecov-commenter]

Codecov Report

Base: 40.46% // Head: 40.52% // Increases project coverage by +0.05% 🎉

Coverage data is based on head (e420852) compared to base (85b578a).
Patch coverage: 57.14% of modified lines in pull request are covered.

❗ Current head e420852 differs from pull request most recent head 8cb2e49. Consider uploading reports for the commit 8cb2e49 to get more accurate results

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #477      +/-   ##
==========================================
+ Coverage   40.46%   40.52%   +0.05%     
==========================================
  Files           7        7              
  Lines        2696     2697       +1     
==========================================
+ Hits         1091     1093       +2     
+ Misses       1605     1604       -1     

Impacted Files	Coverage Δ
src/GR.jl	30.59% <57.14%> (+0.20%)	⬆️

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[t-bltg]

@jheinen, once confirmed can you merge and release 0.69.4 (or maybe give me write rights to this repo) ? Sorry for disturbing your holidays.

Even better, GR.jl could be transferred to the JuliaPlots organization for easier maintenance (since it is the primary Plots backend).

[BioTurboNick]

Confirmed, works on Windows.

[jheinen]

Thanks for the PR.