Tweak completion filtering behavior. #2

Show object creation completion before braces

Fix race conditions caused by doing something *after* the corresponding symbol completion bit was set. (#16740)

* Fix race conditions caused by doing something *after* the corresponding symbol completion bit was set.
Fixes #16706

Show `base` keyword within expression-bodied accessors

lower server stream buffer size.

Arrow-expression-bodies should auto-collapse when 'collapse to definitions' is invoked.

Add missed code style options to automation object

* allow use of a byref parameter inside of nameof

* remove random whitespace changes

* add handling for linq queries

* And -> AndAlso

* change name of linq query

* add linq assembly ref

Adrian was reporting high LOH fragmentation in OOP process due to this. I did some experiment and lowered buffer size to 12K that seems keeping current synch perf similar to now but way lower buffer size.

Fixed crashes when there are multiple type forwarders for the same type

Merge branch 'post-dev15' of https://www.github.com/dotnet/roslyn into fix-16484-duplicate-forwarders-in-metadata-big

* remove no-arg-constructors for ArgumentException from compiler

* fix all `new ArgumentException(nameof(paramname))` instances.

* update error

* remove IManagedPointerTypeReference

* re-add namespace type

* fix whitespace

added error which only build support

Revert "Revert StreamJson" change

handle HubClient cancellation exception

Respect debugger suggestion mode settings

Allow publishing post-dev15 branch

Reduce memory consumption of LongestCommonSubsequence