ExtensionManager: Guard usage of __DATE__

Use __DATE__ only if no reproducible build is required.
Don't show a date in the ExtensionManager if there is none.

Amends: 07000281da

Change-Id: I419ce742c6c7358d7a294ea4d239aca07ef7890e
Reviewed-by: Eike Ziller <eike.ziller@qt.io>

src/plugins/extensionmanager/extensionmanagerwidget.cpp

@@ -609,7 +609,11 @@ void ExtensionManagerWidget::updateView(const QModelIndex &current)
         };
 
         const QDate dateUpdated = current.data(RoleDateUpdated).toDate();
+        const bool hasDateUpdated = dateUpdated.isValid();
+        if (hasDateUpdated)
             m_dateUpdated->setText(dateUpdated.toString());
+        m_dateUpdatedTitle->setVisible(hasDateUpdated);
+        m_dateUpdated->setVisible(hasDateUpdated);
 
         const QStringList tags = current.data(RoleTags).toStringList();
         m_tags->setTags(tags);

src/plugins/extensionmanager/extensionsmodel.cpp

@@ -209,8 +209,10 @@ QVariant ExtensionsModelPrivate::dataFromLocalPlugin(int index, int role) const
                                           : QStringList(platformsPattern);
         return platforms;
     }
+#ifdef QTC_SHOW_BUILD_DATE
     case RoleDateUpdated:
         return QDate::fromString(QLatin1String(__DATE__), "MMM dd yyyy");
+#endif
     case RoleVendor:
         return pluginSpec->vendor();
     case RoleVendorId: