extensions/git/src/model.ts/Model/registerRemoteSourceProvider
class Model:	registerRemoteSourceProvider(provider: RemoteSourceProvider): Disposable {
		this.remoteSourceProviders.add(provider);
		this._onDidAddRemoteSourceProvider.fire(provider);

		return toDisposable(() => {
			this.remoteSourceProviders.delete(provider);
			this._onDidRemoveRemoteSourceProvider.fire(provider);
		});
	}