Remove useless setParent call and related condition.

[rhuanjl]

Follow up to issue: #3638

The issue was already fixed by removing the unnecessary assert:
#4548

But - it highlighted another small issue. The setParent call in JsrtCore is useless - it results in several operations all of which have no useful end result.

(No test case included as this doesn't fix a bug it just removes useless code)

[obastemur]

/cc @akroshg

[rhuanjl]

Small extra comment on this - additional to not doing anything useful this extra setParent command generated noise that made debugging some of the recently fixed module issues harder than it would otherwise have been.

[akroshg]

This seems to be fine with me - although I'd ask @boingoing for the confirmation.

[rhuanjl]

@boingoing please could you take a look when you have a minute? This code is a rather annoying noise generator.

[boingoing]

Sounds reasonable to me. Can we assert here that the child module has parent set to the referencing module?

[rhuanjl]

We should not assert here - it will fail. The child module record should never have a parent set at this point - this is the first of the two places it's currently set (and it's the wrong one.)

Steps in process:

1. CC identifies that parent module has dependency and notifies host to fetch the child module:
   https://github.com/Microsoft/ChakraCore/blob/master/lib/Runtime/Language/SourceTextModuleRecord.cpp#L769

2. (assuming module not already loaded) Host Initialises a module record with JsInitialiseModuleRecord which we're looking at here and returns it.

3. CC then sets the parent:
   https://github.com/Microsoft/ChakraCore/blob/master/lib/Runtime/Language/SourceTextModuleRecord.cpp#L774-L779

Setting the parent in JsInitialiseModuleRecord is premature as it's about to be set within ResolveExternalModuleDependencies. Additionally as the dependency handling is all done with un-normalised specifiers whereas this set in JsInitialiseModuleRecord is done with a normalised specifier it therefore results in doubling up - as the two names may well not be the same.

[boingoing]

Alright, I see what you mean. Seems fine to me.

[rhuanjl]

@boingoing let me know if this should be rebased to master and/or if you want me to do anything else with it.

[boingoing]

This change should retarget master. 👍

[rhuanjl]

@boingoing I've rebased to master and updated. please let me know if you'd like me to do anything else with this.

[boingoing]

I will do some internal testing and pull in the change. 👍