Merge release/dev16.2-preview1 to master

Fix the master build

Merge release/dev16.1 to release/dev16.2-preview1

Merge release/dev16.2-preview1 to master

This reverts commit 3bdbd560.

Pattern System.Index indexers currently call GetOffset on the System.Index
argument, even if the argument is hat operator. If the argument is a hat
operator, we can skip the creation of the intermediate System.Index type
and directly emit the offset calculation.

Inverted condition caused us to crash instead of giving an error message
when calling an indexer with a bad input type.

Fixes #35622

Fix metadata to project reference conversion bugs

Fix commit of import completion

Revert "Make compilation outputs available via a workspace service (#34809)"

Fix three .editorconfig bugs

Move to a newer version of CoreCLR

Microsoft.NETCore.App 3.0.0-preview6-27706-07, SDK version 3.0.100-preview6-011773

This reverts commit 3bdbd560.

We used to do this when we used StyleCop, as this was a way to silence
complaints about using hungarian notation. We don't use StyleCop
anymore, so it's moot.

Prior to 7e10f449 we had a hack which
worked around more proper project for fetching ref paths; when looking
for possible references to convert to project references, we just
stripped the ref subfolder off of a path and then compared that way.
The intent was then to fix up proper support by correctly fetching
the ref paths when that's available, but then we missed actually
fetching it in the legacy project system case.

If a project happened to have the same output path and intermediate
output path, and another project that also had that same path was
removed, we'd get confused that there was only a single project
to reference and would throw when trying to connect everything back up.

When we're converting metadata references to output references, if
there are two projects specifying the same output path, we don't do
conversion and instead just keep the reference to the metadata
reference. This was largely becasue we don't have a way to pick between
the two options, and going with "the first" isn't deterministic. There
was a bug though: when we get a second project with the same output path,
we didn't correctly do the conversion of existing references to the
first back, so you'd end up with that project reference dangling.
do the conversion back to

Without this, the AnalyzerOptions we get from a Project that does
support AnalyzerConfig settings won't be used when running IDE
analyzers.

We have a function that returns all TextDocumentStates held by a
ProjectState so we can process updating file names for all files when
we add and remove an entire project. This needed updating for
AnalyzerConfigDocuments.

Update PublishData for 16.2 Preview 1

Co-Authored-By: NJason Malinowski <jason@jason-m.com>

Update PreReleaseVersionLabel to beta2 for master

we found a de-dup bug with full solution analysis.

basically, when we get errors, we categorize them as either syntax, semantic or other errors. it works fine for live but errors from build, we don't know what kind of errors they are. so we mark those with most common error kind (semantic) and mark that it is from build so that we can refresh them next time we do live analysis.

with full solution analysis off, it works fine since we fix those up when a file is opened. but for closed file with FSA, we sometimes fail to de-dup correctly due to our refresh optimization.

now we always refresh errors when build error is involved.

A PROTOTYPE comment snuck its way into master. It described some a
possible interpretation for the editorconfig parser on line
continuations, but I don't think we should do it, so the correct fix is
to remove the comment.

Refactor ApplyConversion into VisitConversion