Dashboard breaks on unrestorable session state in URL

[flash1293]

Kibana version: >= 7.7

Describe the bug: When accessing a dashboard URL having state:storeInSessionStorage enabled, dashboard fails to render if the state hashes in the URL can't be resolved.

Steps to reproduce:

1. Enable state:storeInSessionStorage
2. Go to a dashboard
3. Open a new incognito tab (or tab in another browser) and copy/paste the URL from your main tab
4. Empty page renders

Expected behavior:
The dashboard should render based on the saved object state and a toast should be shown informing the user the URL state could not the restored.

Any additional context:
Stack trace:

angular.js:15570 Error: Unable to completely restore the URL, be sure to use the share functionality.
    at throwUnableToRestoreUrlError (state_hash.ts:50)
    at retrieveState (state_hash.ts:56)
    at decodeState (encode_decode_state.ts:27)
    at kbn_url_storage.ts:44
    at Array.forEach (<anonymous>)
    at getStatesFromKbnUrl (kbn_url_storage.ts:43)
    at getStateFromKbnUrl (kbn_url_storage.ts:60)
    at Object.get (create_kbn_url_state_storage.ts:62)
    at new DashboardStateManager (dashboard_state_manager.ts:99)
    at new DashboardAppController (dashboard_app_controller.tsx:114) "<div ng-view="" class="dshAppContainer ng-scope">"

This is the line throwing the error:https://github.com/flash1293/kibana/blob/bf04235dae35452061cc7ea3d86d96c19a58206c/src/plugins/dashboard/public/application/dashboard_state_manager.ts#L132

It should be guarded with a try/catch block - if the URL state can't be restored, it should just continue the initialization routine based on the state it already got from the saved object.

As Visualize and Discover are using very similar state handling mechanisms, they are most likely affected by this as well and should be fixed the same way.

[elasticmachine]

Pinging @elastic/kibana-app (Team:KibanaApp)

[inqueue]

The same is reproduced when right clicking the Visualize field link from the Discover app to visualize in a new tab.

[flash1293]

Good catch @inqueue , it's using a very similar technique for state handling. I updated the description.

[flash1293]

cc @Dosant - one option would be to handle this error case within the state management helper from utils by just returning undefined and showing the toast, wdyt? Then we could fix all cases of this at once.

[Dosant]

@flash1293, I agree this should be better handled inside the util, but I'd also prefer to not pass toastService inside of it.

Anyway, because it isn't a plugin, but just a set of stateless functions, will have to pass something everywhere explicitly. So maybe make it more generic at allow to pass onError function?

It also not only about try / catching initial get function. I think if error happens during subsequent syncing, it just crashes now and observables inside state containers error out - so anyway improvements are needed inside the utils

I think we should put generic error handling improvements on app-arch roadmap, but if we want to fix this asap I think at least try / catch initial get would be a good improvement.

[elasticmachine]

Pinging @elastic/kibana-app-arch (Team:AppArch)