src/vs/workbench/contrib/extensions/browser/extensionsActions.ts/SetProductIconThemeAction/computeEnablement
class SetProductIconThemeAction:	private computeEnablement(productIconThemes: IWorkbenchProductIconTheme[]): boolean {
		return !!this.extension && this.extension.state === ExtensionState.Installed && this.extensionEnablementService.isEnabledEnablementState(this.extension.enablementState) && productIconThemes.some(th => isThemeFromExtension(th, this.extension));
	}