(core) Hide workspace in breadcrumbs if doc is unsaved

Summary:
Hides the workspace in the breadcrumbs menu if
the doc is unsaved and is not a fork. In practice,
this should usually be when an anonymous user creates a new
document.

Test Plan: Browser tests.

Reviewers: dsagal

Reviewed By: dsagal

Differential Revision: https://phab.getgrist.com/D2967

app/client/ui/TopBar.ts

@@ -47,6 +47,7 @@ export function createTopBarDoc(owner: MultiHolder, appModel: AppModel, pageMode
           isPageNameReadOnly: (use) => use(gristDoc.isReadonly) || typeof use(gristDoc.activeViewId) !== 'number',
           isDocNameReadOnly: (use) => use(gristDoc.isReadonly) || use(pageModel.isFork),
           isFork: pageModel.isFork,
+          isBareFork: pageModel.isBareFork,
           isRecoveryMode: pageModel.isRecoveryMode,
           userOverride: pageModel.userOverride,
           isFiddle: Computed.create(owner, (use) => use(pageModel.isPrefork)),

app/client/ui2018/breadcrumbs.ts

@@ -106,6 +106,7 @@ export function docBreadcrumbs(
     isDocNameReadOnly?: BindableValue<boolean>,
     isPageNameReadOnly?: BindableValue<boolean>,
     isFork: Observable<boolean>,
+    isBareFork: Observable<boolean>,
     isFiddle: Observable<boolean>,
     isRecoveryMode: Observable<boolean>,
     userOverride: Observable<UserOverride|null>,
@@ -114,25 +115,31 @@ export function docBreadcrumbs(
   }
   ): Element {
     return cssBreadcrumbs(
-      cssIcon('Home',
+      dom.domComputed<[boolean, PartialWorkspace|null]>(
+        (use) => [use(options.isBareFork), use(workspace)],
+        ([isBareFork, ws]) => {
+          if (isBareFork || !ws) { return null; }
+          return [
+            cssIcon('Home',
               testId('bc-home'),
               cssHideForNarrowScreen.cls('')),
-      dom.maybe(workspace, _workspace => [
-        cssWorkspaceName(
-          urlState().setLinkUrl({ws: _workspace.id}),
-          dom.text(_workspace.name),
-          testId('bc-workspace'),
-          cssHideForNarrowScreen.cls('')
-        ),
-        cssWorkspaceNarrowScreen(
-          'Expand',
-          urlState().setLinkUrl({ws: _workspace.id}),
-          testId('bc-workspace-ns')
-        ),
-        separator(' / ',
-                  testId('bc-separator'),
-                  cssHideForNarrowScreen.cls(''))
-      ]),
+            cssWorkspaceName(
+              urlState().setLinkUrl({ws: ws.id}),
+              dom.text(ws.name),
+              testId('bc-workspace'),
+              cssHideForNarrowScreen.cls('')
+            ),
+            cssWorkspaceNarrowScreen(
+              'Expand',
+              urlState().setLinkUrl({ws: ws.id}),
+              testId('bc-workspace-ns')
+            ),
+            separator(' / ',
+                      testId('bc-separator'),
+                      cssHideForNarrowScreen.cls(''))
+          ];
+        }
+      ),
       editableLabel(
         docName, options.docNameSave, testId('bc-doc'), cssEditableName.cls(''),
         dom.boolAttr('disabled', options.isDocNameReadOnly || false),