src/vs/platform/contextkey/browser/contextKeyService.ts/AbstractContextKeyService/setContext
class AbstractContextKeyService:	public setContext(key: string, value: any): void {
		if (this._isDisposed) {
			return;
		}
		const myContext = this.getContextValuesContainer(this._myContextId);
		if (!myContext) {
			return;
		}
		if (myContext.setValue(key, value)) {
			this._onDidChangeContext.fire(new SimpleContextKeyChangeEvent(key));
		}
	}