Make OSX 10.11 usage explicit (#17483)

Fix SolutionLoadEvents

So, it turns out that when you AdviseSolutionEvents, the shell actually
checks the same object for all of the related solution events interfaces
to fire events to them. This meant that after commit
e6a43cb5, we never actually received any
IVsSolutionLoadEvents or IVsSolutionWorkingFoldersEvents. The impact of
this is that we never called "FinishLoad" to populate the Roslyn
workspace with the projects that had been loaded.

Most features would appear to work, as we would load a project and it's
dependencies when a file was opened, but we would then not load any
thing that depends on it, so features like Find All References and
Rename wouldn't work reliably.

Fixes
https://devdiv.visualstudio.com/DevDiv/_workitems?_a=edit&id=389698.

Move IVsSolutionEvents to VisualStudioWorkspaceImpl

send servicehub log files along with NFW to help investigate HubClient.RequestServiceAsync issues.

This is important because the solution state can be different from the
global state, and fetching it in OnAfterSolutionClosed() will get the
global value, not the per-solution one.

In Lightweight solution load, we depend on
IVsSolutionEvents.OnAfterOpenSolution being called to populate the
workspace and create projects.  However we were subscribing from
VisualStudioProjectTracker, which we defer create until a project is
opened.  This meant we never got the event for the first time a solution
was opened, and so we failed to populate the workspace.

* do perf tests on other branches

* fix branc hname

* use branchName

Update to publish dev15.0.x

This is just two branches that are currently configured to be building
2.0 and 2.1 packages.

let OOP to be killed

Get the open vs-integration tests running.

Update the VisualStudioInstanceFactory to close the _currentlyRunningInstance before setting it to null.

Ensure package is loaded by loading CPS project

Capture better dumps for DevDiv #363724

Duplicate some existing scoping tests for pattern declarations in declarator arguments, where they are not permitted. (#16804)

* Duplicate some existing scoping tests for pattern declarations in declarator arguments, where they are not permitted.
Fixes #13660

Remove space preventing editorconfig settings from applying to vb files

Downgrade SyntaxVisualizerExtension dependencies

Bump the NuGet moniker to -rc5

We've shipped -rc4 packages to nuget.org, so any future builds should
be versioned higher.

Capture better dumps for https://devdiv.visualstudio.com/DevDiv/_workitems?id=363724&fullScreen=true&_a=edit

Very infrequently, ImplementsClauseCompletionProvider is asked to provide symbols with a null context. It's not clear why this would happen. Add a FatalError.Report if we try to call any provider with a null context.

Merging on behalf of @DanMcNultyDev

Add test coverage for Out Vars in global code in remaining executable statements.

Added test to verify intellisense on Enumerable.Join parameter types

Closes #14113.

More pattern matching scope tests