Fix AsyncLazy CancellationToken handling

Mitigate memory leak and disable affected tests

All the disabled tests are associated with issue #759 which tracks
re-enabling these.

When we were cancelling tasks returned from GetValueAsync, we were
not passing along the CancellationToken because TaskCompletionSource
doesn't allow us to pass that in .NET 4.5. The appropriate method was
added in .NET 4.6 but we haven't moved to it yet. In the mean time
we'll just use AsyncTaskMethodBuilder which does provide the
necessary functionality.

Fixes GitHub issue #447.

Use C# 6 idioms like => method bodies and string interpolation

Don't suggest events to override in VB

Fixes #715 

update Roslyn.Services.Editor.VisualBasic.UnitTests.dll unit tests to use localized resources

Use absolute path in DiaSymReader nuget pack command

VB does not support virtual events.

Introduce an abstraction layer over PDB imports

Handle parenthesis expansion and simplification in C# interpolations. Fixes Issue #724.

Use Microsoft.NetFX20 package in ResultProviders

In the dev12 PDB format, usings and imports were encoded as strings in
PDB files.  The strings were structured, but required a certain amount of
guesswork (for example, you might not know whether you were importing a
type or a namespace until after binding).  In the new PDB format, usings
and imports are represented as structured blobs and tokens are used
wherever possible.

This change introduces two new class hierarchies, ImportRecord and
ExternAliasRecord, that the expression compiler can pass around instead
of raw strings.  Unfortunately, there is still switching logic in two
places - both when these types are instantiated and when they are
consumed.  The instantiation switch is very simple - we just check for
the appropriate version of ISymUnmanagedReaderX.  The consumption logic
is more complex, because the new and old representations differ
substantially.

TODO: Presently, there is very little code for consuming the new PDB
format, since the APIs are not yet available.

In string interpolations, parentheses can't be removed if they surround
some expression that includes a : or :: token. Othewise, a parsing
ambuity will be introduced due to the : that delimits the format clause
(i.e. $"{number:x4}").

Fixes Issue #724.

Fix spelling the pattern matcher, and avoid recomputing already computed...

Format on Typing Colon For Switch Case Default and Labels

When you call GetValue or GetValueAsync, it's possible that the
method may throw OperationCanceledException if you are the only
requestor and the request is cancelled during your call. In this
case we need to ensure that the token associated with the exception
is the CancellationToken that you passed in instead of the computation
token that we created.

AsyncLazy no longer calls computation functions under the lock.

Fix to VB pretty-listing of line continuation characters in interpolations.

The VB pretty-lister shouldn't remove line continuation characters after
the opening brace or before the closing brace of an interpolated string.
In addition, I found that the pretty-lister was greedily removing line
continuation characters in error conditions where a missing token was
inserted by the compiler to represent the list token of a statement.

Dual-build Microsoft.DiaSymReader -- Net20 and Portable Profile 7

This change addresses #259: below issues related to diagnostics generated for analyzer exceptions from third party analyzers.

1.Suppression of duplicate exception diagnostics: Current mechanism did the suppression in SuppressMessageState based on unique reported messages. This is obviously incorrect as an exception diagnostic will be reported non-suppressed and suppressed on subsequent queries to SuppressMessageState.IsDiagnosticSuppressed.


2.The IDE diagnostic service has multiple layers where document/project diagnostics are filtered and these analyzer exception diagnostics were getting dropped at various places.


So this change moves the exception diagnostics generation + reporting out of the regular analyzer diagnostic pipeline and in line with analyzer load failure diagnostics reporting in VS:

1.Add an event handler to AnalyzerDriverHelper to report analyzer exception diagnostics to interested clients.


2.Listen to these diagnostic events in IDE diagnostic service and wrap them with relevant workspace/project argument and generate updated events.


3.Add an AbstractHostDiagnosticUpdateSource in Features layer to listen and report analyzer exception diagnostic events from diagnostic service. Additionally, removal of an analyzer reference in workspace will clean up the diagnostics for the analyzers belonging to that analyzer reference.


4.Listen to exception diagnostic events in command line compiler and report as regular diagnostics.


Added typw AbstractHostDiagnosticUpdateSource can be extended in future to report other kind of host diagnostics which are not related to a project/document/analyzer.

Correct System.Windows.Forms.dll casing

update version when factory is removed in error list