We had lots of places doing GetTextAsync() and then blocking, which is
an anti-pattern if we can avoid it. Awhile back we plumbed the ability
to get syntax trees synchronusly in certain places, and so we had
the plumbing to do this. We just never did it.

I suspect "most cases" this was fine because the GetTextAsync was
operating on open files which isn't an issue. But there were a few
places that looked suspicious and it's easier to just do a batch
refactoring.

* Moved VB tests to test emitted attributes vs source synthesized ones

* PR Comments

* Simplify how we do fix all tests.

* Simplify.

Updates to our IOperation testing

Avoid allocating instances of LookupResult in a loop to decrease pressure on the pool in highly multithreaded scenarios. (#26845)

Related to #26779.

Keeping this offline for now until we get to the root of the Spanish
machine issues.

Move Spanish image to RS4

https://github.com/dotnet/core-eng/issues/3420

No longer require conditional compilation in order to run the full
IOperation test suite.

Groovy cleanup

Remove value that is not used in fix all.

This is cleaning up some code needed to bootstrap groovy changes in an
earlier PR:

https://github.com/dotnet/roslyn/pull/26762

Fix our Compiler NuGet dependency list

otherwise, it will pick up IList but Array implementation only support Rank==1 on runtime even if there is no compile time error.

Merge dev15.8-preview1 to master

Merge dev15.7.x to dev15.8-preview1

Merge dev15.8-preview1 to master

Simplify our use of an extension.

Disable procdump on Spanish runs

The data is pointing towards procdump being the cause of our random AVs
during the Spanish runs. Disabling procdump on the Spanish runs as an
experiment to see if it increases stability here.

Desktop signing uses a COM call into the CLR to sign an assembly,
which is not available on Mono or CoreCLR. This change always
uses portable signing by default on Mono as well as CoreCLR.

The runtimes directory needs to be checked in addition to the root
directory. This has the same set of problems with deployed dependencies.

This updates our NuSpec and SWR files to be compliant with the analysis
we are now running over them.

Need to restructure our CI so that we can call build.ps1 from our
test-build-correctness leg not the other way around. This is necessary
as we now examine many other artifacts including NuGet packages.