* made NFW to use runtime callstack rather than callstack from fake exception

also, made WatsonReporter from VS and ServiceHub to share more implementation

* PR feedback.

rather than using null exception which is taken cared by NFW, we explicitly throw exception to have callstack so that it can show up in perfview as well.

* centralize who throws exception if given exception is never thrown.

also, explicitly add runtime callstack in one of reserved slot to make NFW bucketting better.

* fixed tests and added empty callstack test

Also skip another test that failed while skipping the original test

Fixes https://devdiv.visualstudio.com/DevDiv/_workitems/edit/512823

In VB Code Model, we use SyntaxFactory.ParseTypeName/ParseName when
setting the name of an attribute or namespace. Doing this fails to add
elastic trivia the way it is added in all other cases, so setting the
name of a namespace (for example) would remove the newline, creating
broken code. To fix this, we now manually add elastic trivia in these
cases.

C# was already functioning correctly, but it was using
".IdentifierName()" to parse dotted names, which isn't advised. This
change also updates the C# side accordingly.

This shows our informational version in Help > About instead of a
useless ProductID GUID.

Fixes dotnet/roslyn#17038.

* made NFW to bucket things better

NFW API allows caller to supply extra info to make bucketting better.

this takes advantage of that ability for certain exception types which we know inner or remote exception is more important than the generic outter exception.

* added more comments

* made NFW to bucket things better

NFW API allows caller to supply extra info to make bucketting better.

this takes advantage of that ability for certain exception types which we know inner or remote exception is more important than the generic outter exception.

* added more comments

Fixes #22244
Related to #22406

We don't need the split anymore now that we're only supporting Dev15.

Unfortunately this required the introduction of a NuGet package that
has a namespace "Workspace" to our VS project, which meant I had to
disambiguate Workspace wherever it's used in that layer. I considered
doing an extern alias instead to disambiguate, but applying that to a
ProjectReference isn't supported. That's tracked by NuGet/Home#4989.

The continued mixing of assets between net46 and net461 was causing a
huge number of binding redirect issues in our test assets. Need to move
everything to a consistent 461 to avoid this.

This primarily moves us to the 2.2.0 version of xunit. In order to make
that transition though a number of other changes needed to happen as
well:

1. Needed to move our desktop target to 4.6.1. This should've been
required some time ago but we were essentially depending on bugs in the
SDK / NuGet.
1. Remove the DeployCoreClrTestRuntime project. This entire idea
depended on having the xunit.console.netcore package. This has since
been deleted and doesn't work with the 2.0 SDK.
1. Remove the deploy compiler tools project. Can just use dotnet exec
now and that's much more efficient.
1. Resolve a new ambiguity with KeyValuePair. A helper of ours now
exists in netcoreapp2.0.

I fully expect a number of Jenkins legs to fail with this change: build
correctness, coreclr and ubuntu. But I want to validate our other legs
and am still trackind down answers needed to fix the others.

Better error reporting for VsLanguageDebugInfo

* Rename Foo to Goo

* Rename ifoo to igoo

* Add back BOMs

The most recent preview of 15.3 introduced a number of NuGet warnings
into our build. Most of these were due to new dependencies in the
service hub layer. This change fixes these warnings by moving to a new
version of StreamJsonRpc and adding new PackageReferences as dictated by
the warnings

Relevant links:

- https://github.com/NuGet/Home/issues/5633
- https://github.com/NuGet/Home/wiki/Warnings-and-Errors-Combined-Specs

xunit.analyzers will flag public methods of types that have other
facts in them. Sometimes this catches things we missed [Fact] on, and
in other times was catching private test helpers. Make both of the
fixes.

If you had a F# project opened with the new project system, it'd supply
an output directory which other projects (like C#) could reference.
If you had a C# project that referenced the F# project, any attempt
to get the C# compilation would crash because we can't actually produce
F# compilations. The fix is simple: don't convert from metadata
references.

In the new SDK we no longer have a need for ProjectGuid. This change
will:

- Remove ProjectGuid from project files
- Remove Name + Project items from ProjectReference entries
- Change BuildBoss to enforce both of these items