Fix TS 2.4 Errors in extHost.api.impl.ts

[mjbvz]

Errors
In extHost.api.impl.ts:

[14:20:06] Error: /Users/matb/projects/vscode/src/vs/workbench/api/node/extHost.api.impl.ts(121,63): Type 'ExtHostSCM' does not satisfy the constraint 'ExtHostSCMShape'.
  Types of property '$provideOriginalResource' are incompatible.
    Type '(sourceControlHandle: number, uri: URI) => TPromise<Uri>' is not assignable to type '(sourceControlHandle: number, uri: URI) => TPromise<URI>'.
      Type 'TPromise<Uri>' is not assignable to type 'TPromise<URI>'.
        Type 'Uri' is not assignable to type 'URI'.
          Property '_scheme' is missing in type 'Uri'.
[14:20:06] Error: /Users/matb/projects/vscode/src/vs/workbench/api/node/extHost.api.impl.ts(300,9): Type '{ readonly activeTextEditor: ExtHostTextEditor; readonly visibleTextEditors: TextEditor[]; showTe...' is not assignable to type 'typeof window'.
  Types of property 'showInformationMessage' are incompatible.
    Type '(message: any, first: any, ...rest: any[]) => Thenable<string | MessageItem>' is not assignable to type '{ (message: string, ...items: string[]): Thenable<string>; (message: string, options: MessageOpti...'.
      Type 'Thenable<string | MessageItem>' is not assignable to type 'Thenable<string>'.
        Type 'string | MessageItem' is not assignable to type 'string'.
          Type 'MessageItem' is not assignable to type 'string'.
[14:20:06] Error: /Users/matb/projects/vscode/src/vs/workbench/api/node/extHost.api.impl.ts(378,9): Type '{ rootPath: string; asRelativePath: (pathOrUri: string | Uri) => string; findFiles: (include: str...' is not assignable to type 'typeof workspace'.
  Types of property 'onDidChangeConfiguration' are incompatible.
    Type '(listener: () => any, thisArgs?: any, disposables?: Disposable[]) => IDisposable' is not assignable to type 'Event<void>'.
      Types of parameters 'listener' and 'listener' are incompatible.

How to investigate

• Install TS 2.4 in the vscode workspace by running npm install typescript@next
• Make sure vscode is using the workspace version of TS for error reporting by running the Select TypeScript versions command

[joaomoreno]

I fixed the first and third errors.

The second one is a TypeScript bug, IMO. Check this out:

declare function bar(): string | number;

declare namespace foo {
	export function bar(): string;
	export function bar(): number;
}

const obj: typeof foo = {
	bar() {
		return bar();
	}
}

TypeScript 2.4 can't match the type of obj with foo, which seems to be to be incorrect.

[mjbvz]

Thanks. I believe this is the same issue I reported here: microsoft/TypeScript#16412 which itself was marked as a duplicate of microsoft/TypeScript#14107

Not sure what the best workaround is in this case. Let me take another look

[mjbvz]

Not seeing errors using 2.4 RC anymore