fix(typescript-estree): persisted parse and module none

[armano2]

This PR fixes issue when persisted parse is called with module option set to "none",

fixes #1502

[bradzacher]

I just assumed we always needed to set the parent pointers.
The thing I hate is that this method has side-effects, and we can't just call a method to set parent pointers.

cc @uniqueiniquity for "when we need to call it"

[armano2]

Typescript actually calls this function to "fix" parent nodes.

https://github.com/microsoft/TypeScript/blob/9ba45fcaace07510ef259d4cda2bc5ec523cf6d1/src/compiler/parser.ts#L887-L917

normally parent references are set during binding. However, for clients that only need a syntax tree, and no semantic features, then the binding process is an unnecessary overhead. This functions allows us to set all the parents, without all the expense of binding.

[armano2]

i'm tempted to remove calls to parent node from converter as we are already traversing nodes,
that should allow me to remove this code and remove it from other places

currently in all other parsing modes we are setting up setParentNodes property as true to get this fixed just for this,

Update:
few missing comments about parent nodes are added

[codecov]

Codecov Report

Merging #1516 into master will increase coverage by <.01%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master    #1516      +/-   ##
==========================================
+ Coverage   95.42%   95.42%   +<.01%     
==========================================
  Files         140      140              
  Lines        6400     6401       +1     
  Branches     1832     1832              
==========================================
+ Hits         6107     6108       +1     
  Misses        108      108              
  Partials      185      185

Impacted Files	Coverage Δ
...estree/src/create-program/createIsolatedProgram.ts	75% <ø> (ø)	⬆️
...-estree/src/create-program/createDefaultProgram.ts	76.19% <100%> (ø)	⬆️
...pt-estree/src/create-program/createWatchProgram.ts	92.39% <100%> (+0.04%)	⬆️

[bradzacher]

LGTM - thanks for fixing this