This should either be defined globally or not at all.  Repeating all the logic on a local level is just wasted time.

TLDR: artifacts are going to move around in Binaries\Debug and the directory is going to get a lot bigger.

At a high level build projects can be classified into three categories based on how they write output:

- incorrect: a given output path is written to more than once with different contents
- less correct: a given output path is written to more than once but always with the same content
- correct: a given output path is written to exactly once

Today the roslyn build is decidedly “incorrect” as pretty much every file is written directly into Binaries\Debug. This means it ends up writing pretty much every Visual Studio SDK DLL twice: once for Dev14 and once for Dev15. For example at various points in the build Binaries\Debug\Microsoft.VisualStudio.Text.Data.dll may refer to Dev14 and at others it’s Dev15. If this seems like a scary proposition for a build that’s because it is indeed scary and it has real consequences. By now pretty much everyone on the team has hit the build race condition that is dragging down our PRs.

The general fix here is to move build outputs into separate directories. Instead of building to $(Configuration) projects now build into say $(Configuration)\Exes\$(MSBuildProjectFileName). This will have a substantial increase in the size of Binaries. We will be looking into ways to reduce that. In the short term though build stability far outweighs the size increase.

This change takes us most of the way to "correct". There are several places I had to compromise in order to get this initial change in:

- UnitTests still build to a common output folder (one for Dev14, another for Dev15). Pulling unit tests apart is going to take a bit of work.
- Every project has a <RoslynProjectType> entry. This will go away in the future for most projects. It's temporarily needed so I can fix roslyn-internal in parallel without taking down the build.
- VSL.Imports.targets is messy. Unavoidable for now due to the above. It will get cleaner as I iterate on this.

None of these are relevant to the underlying race condition. Hence it's okay to push them off.

updated build and test to recognize Dev15Tests

re-arranged test export provider

.. Prefer Intrinsic Type codestyle.

The ImportGroup element is just noise.  It was also used very inconsistently in the repo and often within the same project file.  Just remove it.

AbstractMoveTypeTest

AbstractMoveTypeTestsBase implements shared helpers for testing MoveType
Refactoring.

CSharpMoveTypeTestsBase and BasicMoveTypeTestsBase contain language
specific test helpers.

Tests are organized as MoveTypeTests.<CodeAction>.cs/vb

where code actions are
Move type to new file
Rename type to match filename
Rename file to match typename etc.

The feature code is mostly language agnostic, so it suffices if we pick
one language and test it heavily and make sure simple things and
language specific parts work as expected, on the other language.

* Merge pull request #12041 from heejaechang/buildsyncrace

found one more case where documentId can be null

* prevent VS from crashing if VS got shutdown while build error reporting is in progress.

* Update our NuGet package version to 1.3.2

* Update Microsoft.DiaSymReader.Native to 1.4.0 RTM (#12141)

* Enable building of release nuget packages.

This commit makes it so that we will always try to generate release nugets except if they depend on prerelease packages. If one of our nuget packages happens to depend on prerelease packages, then when building release nugets, we will simply print a message in the build output and skip release nuget generation for that package (and allow the overall build to succeed).

* Address code review feedback.

* Simplify script to use nuget.exe for prerelease dependency validation instead of adding custom logic in the script for this.

* Remove Microsoft.CodeAnalysis.EditorFeatures from list of prerelease nuget packages.

* Change the name of the error log file to skipped_packages.txt.

* fixed DifferenceViewer leak

this leak was responsible for about 14% of managed memory in customer's dump.

basically, in certain condition, if cancellation exception is thrown, we will not close difference viewer which cause
all text views to leak. that cause all taggers and text buffers to leak and that cause our preview workspaces to alive.
which in turn cause all solutions to alive and so on. all those objects (view, buffer, workspace, solution) are quite
big graphs. so ends up eat up 14% of memory.

added assert to make sure if we leak viewers again, we get some kind of notification.

this leak was responsible for about 14% of managed memory in customer's dump.

basically, in certain condition, if cancellation exception is thrown, we will not close difference viewer which cause
all text views to leak. that cause all taggers and text buffers to leak and that cause our preview workspaces to alive.
which in turn cause all solutions to alive and so on. all those objects (view, buffer, workspace, solution) are quite
big graphs. so ends up eat up 14% of memory.

added assert to make sure if we leak viewers again, we get some kind of notification.

Fixes https://github.com/dotnet/roslyn/issues/11464

1. Reference a bunch of stuff from Nuget packages instead of VS.
2. Move to Update 2 versions of packages.
3. Now that we are using the packages, we're referencing
   Microsoft.VisualStudio.Shell.14.dll instead of .15 again.  This means
   that types that moved to Shell.Immutable.15 are not type forwarders.
   Luckily we didn't need anything from Shell.Immutable.15 in the project
   where it was a problem.

This brought along some references to Microsoft.VisualStudio.Threading
that we previously didn't have. Nothing was wrong with this, but it
meant I had to fix some namespace qualifications that were assuming the
"Threading" namespace was unambiguous.

Revert "Revert "Disable diagnostic service for projects that we know we don't have all information to provide good results.""

Revert "Disable diagnostic service for projects that we know we don't have all information to provide good results."

This allows us to build with Update 2 installed, where the version number
is different.

this should make roslyn to turn off full project diagnostics when intellisense build is failed for the project.

when we detect intellisense build failure, VS should put actionable data in error list detail pane.
also bing search for the issue should work as well if one prefer blogs.

this change also fix some issue on cross language p2p references. before there was case where we fail to connect cross language p2p reference causing a lot of errors.

this change also include bulk diagnostic update events improvement. this should let us to deal better (especially when we clean those up) when there are a lot of diagnostics.

This allows us to build with Update 2 installed, where the version number
is different.

1. Drop "is" for some names
2. CommentBlock -> BlockComment

Plus a little clean up.

Expose test internals for ResetInteractive tests.

Adds a disposable wrapper around ITextView to avoid writing try ...
finally... everywhere.

Move tests to editor layer.  They test code that should only be called from the UI thread, so we need [WpfFact]