* Fix more Compiler Errors for TS 2.4 in the VSCode codebase

* Fix compile error for 2.3

From: https://github.com/Microsoft/TypeScript/issues/15352

TS 2.3.1 introduced a breaking change by [switching to covariant types for callbacks](https://github.com/Microsoft/TypeScript/wiki/Breaking-Changes#covariance-in-callback-parameters). This change tries to fix these compiler errors in the workbench codebase

TS 2.3.1 introduced a breaking change by [switching to covariant types for callbacks](https://github.com/Microsoft/TypeScript/wiki/Breaking-Changes#covariance-in-callback-parameters). This change tries to fix these compiler errors in the workbench codebase

Show more error messages from rg. For #24050, but we will also update rg to get a better error message for bad globs.

Queuing a large number of WinJS promises that aren't actually async can lead to a stack overflow. Also this is faster.

Remove OutputService reference from SearchService, this should be handled elsewhere

Tested recomppiling VSCode with TS2.3. This fixes a few issues that were discovered, including workarounds for:

* https://github.com/Microsoft/TypeScript/issues/15184
* https://github.com/Microsoft/TypeScript/issues/15185

For debugging purposes and transparency.