8368966: Remove spurious VMStructs friends

[fandreuz]

In this PR I propose a small clean up to remove several spurious friends of VMStructs. Either I could not find any reference to them in vmStructs*, or no private symbols is mentioned.

Passes tier1 and tier2 (fastdebug).

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• JDK-8368966: Remove spurious VMStructs friends (Enhancement - P4)

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• 00: Full (1f873d0d)

[stefank]

I was a bit surprised to see that you added a friend declaration. Was this done because you removed the one in the parent class?

I see that vmStructs.cpp has GrowableArray listed:

  nonstatic_field(GrowableArrayBase,           _len,                                          int)                                   \
  nonstatic_field(GrowableArrayBase,           _capacity,                                     int)                                   \
  nonstatic_field(GrowableArray<int>,          _data,                                         int*) 

So, I guess it makes sense to move it here. OTOH, the exposed _data field is inside GrowableArrayView, so maybe it would work to put the friend declaration there instead?

I guess either way is fine but there's a risk that there will be some churn about where to put the friend declaration if someone wants add one of the classes between (and including) GrowableArrayView and GrowableArray.

[fandreuz]

Was this done because you removed the one in the parent class?

Yeah that was my reasoning.

I guess either way is fine but there's a risk that there will be some churn about where to put the friend declaration if someone wants add one of the classes between (and including) GrowableArrayView and GrowableArray.

To me it looks less confusing to have the friend declaration for the type which is referenced in vmStructs. But both are legal, do you think moving the friend declaration to the type which declares the referenced field would be more appropriate? If yes, I'll track other similar patterns too.