Use common output directory for Samples.

[Ask Mode] Fix IOperation crash caused by passing null for ConstantValue when creating Lite…

Ask Mode request: Prevent DeriveArgument from throwing ArrayIndexOutOfRangeException when presented with semantically malformed bound trees.

Disable DocCommentTest Include_Cycle_WRN_XMLDocInvalidXMLFragment

This time it is caused by BontrolVariable bounf to BoundBadExpression.
Also improved the robustness in the Condition property.

EnC: Fix handling ByRef parameters in anonymous delegates

Fix reset interactive build cancellation

Do not offer to create p2p references if the project system will not allow those references.

Prevent DeriveArgument from throwing ArrayIndexOutOfRangeException when presented with semantically malformed bound trees.

Fix an issue in the test caching layer

Update doc comment tests that contain XML comments with paths

The test caching layer had two bugs around re-hydrating the test resutls from cache:

- Made a bad assumption about the name of the file.
- Assumed tests were always rehydrated into the original directory.

closes #8860

Cancel the signature help if the user navigates before it has been presented

Revert "Revert "Merge pull request #7510 from CyrusNajmabadi/analysisSpeedup""

Revert "Merge pull request #7510 from CyrusNajmabadi/analysisSpeedup"

This reverts commit 4ed5b596, reversing
changes made to 29ab8cba.

Ask Mode request: Fix IndexOutOfRangeException when running operation actions over Roslyn sources.

Fix vbc crashing when compiling 0 files into a library 

Ignore dlls that come from a 'packages' directory when searching for viable metadata references to search.

Fixes #8577

Clarify behavior when RunServerCompilation throws an exception

Reuse the SupersedeLowerVersions flag in the EE

Move interactive commands out of InteractiveFeatures

Disable Failing Documentation Tests (Stabilization)

Scripting scenarios set a special flag in the ReferenceManager to enable
additional tie-breaking rules in the presence of conflicting references.
Enable that same flag for the EE, which also routinely encounters
conflicting references.

Fixes internal bug 161294.