src/vs/workbench/services/views/common/viewContainerModel.ts/ViewDescriptorsState/initialize
class ViewDescriptorsState:	private initialize(): Map<string, IViewDescriptorState> {
		const viewStates = new Map<string, IViewDescriptorState>();
		const workspaceViewsStates = this.getStoredWorkspaceState();
		for (const id of Object.keys(workspaceViewsStates)) {
			const workspaceViewState = workspaceViewsStates[id];
			viewStates.set(id, {
				active: false,
				visibleGlobal: undefined,
				visibleWorkspace: isUndefined(workspaceViewState.isHidden) ? undefined : !workspaceViewState.isHidden,
				collapsed: workspaceViewState.collapsed,
				order: workspaceViewState.order,
				size: workspaceViewState.size,
			});
		}

		// Migrate to `viewletStateStorageId`
		const value = this.storageService.get(this.globalViewsStateStorageId, StorageScope.WORKSPACE, '[]');
		const { state: workspaceVisibilityStates } = this.parseStoredGlobalState(value);
		if (workspaceVisibilityStates.size > 0) {
			for (const { id, isHidden } of workspaceVisibilityStates.values()) {
				let viewState = viewStates.get(id);
				// Not migrated to `viewletStateStorageId`
				if (viewState) {
					if (isUndefined(viewState.visibleWorkspace)) {
						viewState.visibleWorkspace = !isHidden;
					}
				} else {
					viewStates.set(id, {
						active: false,
						collapsed: undefined,
						visibleGlobal: undefined,
						visibleWorkspace: !isHidden,
					});
				}
			}
			this.storageService.remove(this.globalViewsStateStorageId, StorageScope.WORKSPACE);
		}

		const { state, hasDuplicates } = this.parseStoredGlobalState(this.globalViewsStatesValue);
		if (hasDuplicates) {
			this.setStoredGlobalState(state);
		}
		for (const { id, isHidden, order } of state.values()) {
			let viewState = viewStates.get(id);
			if (viewState) {
				viewState.visibleGlobal = !isHidden;
				if (!isUndefined(order)) {
					viewState.order = order;
				}
			} else {
				viewStates.set(id, {
					active: false,
					visibleGlobal: !isHidden,
					order,
					collapsed: undefined,
					visibleWorkspace: undefined,
				});
			}
		}
		return viewStates;
	}