We should move the following test cases of TabModelTest to EarlGrey:
- RestoreSessionOnNTPTest
- RestoreSessionOn2NTPTest
- RestoreSessionOnAnyTest

These tests use NavigationManager::CommitPendingItem() to simulate navigations in tabs. With LegacyNavigationManager, this works without an embedded test server because LegacyNavigationManager does not require the navigations to actually succeed in the web view.

With WKBasedNavigation, an embedded test server is required. However, since TabModel is deprecated, it's better to migrate these to EGtest instead of adding embedded test server to tab_model_unittest.

The main blocker is to figure out a way to trigger [TabModel restoreSessionWindow] in EG test without actually using the TabModel API. Currently it is only used in CrashRestoreHelper, which is also not tested in EG test.