Merge changes into release/2.1

[wtgodbe]

CC @mmitche

[wtgodbe]

CC @weshaggard is the change to System.Runtime.CompilerServices.Unsafe in packageindex.json expected? I got this by merging in changes from VSTS.

[wtgodbe]

Note to self - don't squash this

[weshaggard]

This was removed as part of #29970 so I don't think it should be added back.

[stephentoub]

Note to self - don't squash this

How come?

[mmitche]

@stephentoub We want the exact commit we built for 2.1.2 for tagging purposes

[stephentoub]

Ok. That shouldn't require six additional commits.

[wtgodbe]

@stephentoub do you suggest rebasing & squashing the rest of the commits? I'm not sure how to go about doing that, rebasing this against either version of release/2.1 only gave me 2 commits, neither of which were the one I wanted

[mmitche]

You could only squash after the commit you want.

[stephentoub]

squashing the rest of the commits?

Right. Thanks.

[wtgodbe]

This is now in the correct state, we need to maintain the commit chain to get the correct commit hashes.

[stephentoub]

I obviously have a gap in my git knowledge here... what does it mean for the commit that resulted from merging this to be empty?
69120f8

[mmitche]

It means there were no diffs with HEAD of 2.1, but we introduced additional commits into the git tree.

[weshaggard]

I obviously have a gap in my git knowledge here... what does it mean for the commit that resulted from merging this to be empty?

I believe it was a result of a cherry-pick of the same exact change but a different commit. When merged there were no changes just the merges in order to have a matching sha for what we built from.

[stephentoub]

Ok, thanks.