src/vs/workbench/services/extensions/common/abstractExtensionService.ts/AbstractExtensionService/_updateExtensionsOnExtHosts
class AbstractExtensionService:	private async _updateExtensionsOnExtHosts(toAdd: IExtensionDescription[], toRemove: ExtensionIdentifier[]): Promise<void> {

		// Remove old running location
		const removedRunningLocation = new Map<string, ExtensionRunningLocation | null>();
		for (const extensionId of toRemove) {
			const extensionKey = ExtensionIdentifier.toKey(extensionId);
			removedRunningLocation.set(extensionKey, this._runningLocation.get(extensionKey) || null);
			this._runningLocation.delete(extensionKey);
		}

		// Determine new running location
		this._updateRunningLocationForAddedExtensions(toAdd);

		const promises = this._extensionHostManagers.map(
			extHostManager => this._updateExtensionsOnExtHost(extHostManager, toAdd, toRemove, removedRunningLocation)
		);
		await Promise.all(promises);
	}