The contract is to return null if the ProjectId didn't come from us.
If we don't have deferred state, then we're not even initialized so
it most definitely didn't come from us.

In 44142e5f I removed this code, under the belief that it wasn't
a problem. However, when WpfFact-attributed tests run, we clear the
foreground thread. Some static state (namely the
ForegroundNotificationService) is still trying to operate between test
runs, so it'd see the fallback state and then bad things would happen.
Although there's a number of terrifying things there, for now we'll
just roll it back.

Unfortunately CodeLens (and others) might still be doing this, so
we won't assert if it's already been initialized. This is risky but
restores to closer to the original behavior until we can get all
callers updated.

If we try deferring this, we might end up calling it on the first thread
to raise an event, instead of thread that created the workspace, which
was our previous contract. The default implementation looks at whether
there is a SynchronizationContext to determine what the scheduler is
to use, so the change matters.

auto-close a VSO PR that contains no commits

Progression capabilities

Update DSR dependencies to release

Fixes #16531

Stop applying ComVisible attribute to embedded value types.

Build cleanup

Enable test that is passing now.

Closes #14529.

Remove LINQ allocations from FAR item display logic

Merge thread starvation fix into master

Avoid GUID conflicts for Naming Styles Symbol Specifications (causes Naming Styles to not work and the Tools | Options page to not load)

Do not fail in the NamingStyleCodeFix when we cannot find the symbol (causes the failure InfoBar to be shown)

Don't emit casing-related naming violations when the violating character has no casing (making the feature noisy/unusable in other cultures)

make sure we empty out information in solution/project/documentInfo w…

Ensure that we don't break if we recurse into methods during symbol-key reader

Fixes #16585

Restore detection of an ambiguous method type argument inference.

Expand the lifetime of locals declared within CasePatternSwitchLabelSyntax to the entire switch body.

Fixes #16513

Fixes https://devdiv.visualstudio.com/DefaultCollection/DevDiv/_workitems?id=336030
Fixes https://devdiv.visualstudio.com/DefaultCollection/DevDiv/_workitems?id=294570
Fixes https://devdiv.visualstudio.com/DefaultCollection/DevDiv/_workitems?id=363714
Fixes https://devdiv.visualstudio.com/DefaultCollection/DevDiv/_workitems?id=336030
Fixes https://devdiv.visualstudio.com/DefaultCollection/DevDiv/_workitems?id=364165
Fixes #16296
Also adds test for #16559

Change progression providers to use capabilities instead of IntelliSense type. This enables them to work on both .Net core projects and legacy projects.

Revert "Change progression providers to use capabilities instead of IntelliSense type. This enables them to work on both .Net core projects and legacy projects."

This reverts commit 7d4c0da7.

This reverts commit 2209f5cd.

This reverts commit b46607c3.

Fixes https://devdiv.visualstudio.com/DevDiv/_workitems?id=370269.
Releted to #16177.

This uage of .Select is responsible for 1.3% of allocations if you FAR for SyntaxNode.

Expand the lifetime of locals declared within CasePatternSwitchLabelSyntax to the entire switch body.

Fixes #15536.
Fixes #16066.

Fixes #16478.

Fixes #15326, #15486