fix #562, bug in reviving objects when WeakRefs are cleared earlier

[JeffBezanson]

Debugged with @vtjnash . The MWE in the issue works with this, but would be good to get some more testing.

[codecov]

Codecov Report

Merging #569 (dc95f74) into master (52d2f73) will increase coverage by 0.11%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master     #569      +/-   ##
==========================================
+ Coverage   50.15%   50.27%   +0.11%     
==========================================
  Files          32       32              
  Lines        2540     2544       +4     
==========================================
+ Hits         1274     1279       +5     
+ Misses       1266     1265       -1     

Impacted Files	Coverage Δ
src/GLib/gtype.jl	75.63% <100.00%> (+0.41%)	⬆️
src/GLib/gerror.jl	50.00% <0.00%> (+10.00%)	⬆️

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[timholy]

Awesome! I've tested it locally and it seems solid. Let's merge this and get a new release out.

[tknopp]

yea, so much appreciated

[tknopp]

I can confirm that this also fixes a crash within the lab software that we have in my research group. This was the last thing making me hesitate using 1.6 beta. Kudos to @JeffBezanson and @vtjnash. 1.6 will be a fantastic release!