Fix build break by adding missing parens to Vbc task

Revert "Inherit Global Usings from previous submissions"

Inherit Global Usings from previous submissions

Improve compiler behavior around stack overflow caused by long binary expressions.

deal with cases where item in table control is not associated with any project or document

Add PDB format option to /debug flag

Look at the usings for each submission as we visit that submission.  The
mental model is a chain of ```InContainerBinder```s, but we don't actually
instantiate the chain for perf reasons.

TODO: Some tests are failing because of the new semantics.  The main issue
is that usings can now hide members (not just types).  No corresponding
issue exists in C# because usings can't appear within types.

Use correct span to determine block kind

Fixes #5395.

Adjusted Binder, Optimizer, Flow Analysis, code generator and majority of bound tree visitors to not use recursion to handle binary expressions nested on the left side of another binary expression.
Adjusted majority of bound tree visitors to detect that stack overflow is about to happen while an expression is being traversed and report a diagnostic pointing to the expression at fault instead of crashing compiler.

Fixes incorrect codegen where locals could be optimized across implicit branches

Adjustment of the fix for #4471

Property support inference in async lambda/delegates

Fixes #4486

Unbreak End Construct around an broken code scenario

Fix the AnalyzerDependencyChecker to ignore mscorlib

Disable more flaky tests in InteractiveWindowTests

These tests access the clipboard directly in the unit tests and hence
have flaky behavior across machines. Disabling.

See https://github.com/dotnet/roslyn/issues/5544

process all attributes in XML documentation comments

Don't simplify Nullable<T> to T? inside nameof expressions

Allowing insertion of /// or ''' within an XML doc comment on ENTER, even if the option isn't set

Fixes #3020

Detect object initializer pattern inherited from base types

Fixes https://github.com/dotnet/roslyn/issues/4754

fix duplicate test names

Kick off a task to get the initial set of diagnostics when we create the squiggle tagger.

Fixes #5320

Emit dynamic attribute in generated lambda methods

If you hit enter after a Property statement that already had accessors,
but was missing an End Property, we'd get confused of what to do and
not let you do anything at all. That's bad, so now we just do nothing
special and pass it through as an enter. In this case spitting anything
just makes more broken code for the user, so we're best off avoiding
any fanciness.

Fixes #5208.

Remove dependency on csc2 / vbc2

This change removes the compiler server test dependency on csc2 and
vbc2.  These binaries don't exist in all environments where we run these
unit tests as they are no longer a part of the shipping product.
Instead I replaced all uses with csc / vbc and explicitly passed the
shared flag to the compiler.

closes #5550
closes #5557

also special-case the `langword` attribute

Disable flaky tests in InteractiveWindowTests

deterministic switch

have flaky behavior across machines.  Disabling.

See https://github.com/dotnet/roslyn/issues/5544

Add unit tests for expected behavior when 'Generate XML documentation comments for ///' option is not set