* Enable '--strictNullChecks'
* Fix API baselines
* Make sys.getEnvironmentVariable non-nullable
* make properties optional instead of using `| undefined` in thier type
* reportDiagnostics should be required
* Declare firstAccessor as non-nullable
* Make `some` a type guard
* Fix `getEnvironmentVariable` definition in tests
* Pretend transformFlags are always defined
* Fix one more use of sys.getEnvironmentVariable
* `requiredResponse` accepts undefined, remove assertions
* Mark optional properties as optional instead of using `| undefined`
* Mark optional properties as optional instead of using ` | undefined`
* Remove unnecessary null assertions
* Put the bang on the declaration instead of every use
* Make `createMapFromTemplate` require a parameter
* Mark `EmitResult.emittedFiles` and `EmitResult.sourceMaps` as optional
* Plumb through undefined in emitLsit and EmitExpressionList
* `ElementAccessExpression.argumentExpression` can not be `undefined`
* Add overloads for `writeTokenText`
* Make `shouldWriteSeparatingLineTerminator` argument non-nullable
* Make `synthesizedNodeStartsOnNewLine` argument required
* `PropertyAssignment.initializer` cannot be undefined
* Use one `!` at declaration site instead of on every use site
* Capture host in a constant and avoid null assertions
* Remove few more unused assertions
* Update baselines
* Use parameter defaults
* Update baselines
* Fix lint
* Make Symbol#valueDeclaration and Symbol#declarations non-optional to reduce assertions
* Make Node#symbol and Type#symbol non-optional to reduce assertions
* Make `flags` non-nullable to reduce assertions
* Convert some asserts to type guards
* Make `isNonLocalAlias` a type guard
* Add overload for `getSymbolOfNode` for `Declaration`
* Some more `getSymbolOfNode` changes
* Push undefined suppression into `typeToTypeNodeHelper`
* `NodeBuilderContext.tracker` is never `undefined`
* use `Debug.assertDefined`
* Remove unnecessary tag
* Mark `LiteralType.freshType` and `LiteralTupe.regularType` as required
* Add telemetry for open JS files
* Send event every time
* Keep stats even for closed files
* Remove tsCheckCountForOpenFilesTelemetry
* Use 'info.path'
* Update API
This has 3 changes:
1. In updateGraph when enqueue the typing installation request (depending on unresolved imports)
2. When ActionSet event is received, invalidate only files with unresolved imports and resolve those.
3. When ActionInvalidate event is received, typing installer has detected some change in global typing cache location, so just enqueue a new typing installation request. This will repeat the cycle of setting correct typings and pickiing unresolved imports
As with `SetTypings`, new typings have been installed so the project
should be updated and the client should be notified (via event).
Changed PackageInstalledResponse from "event" to "action" for the sake
of explicitness.
Fixes#20084.
