On reset store and allow ignore fragments on removeDirectives

[akiran]

Fix test issues of #2843

[apollo-cla]

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[evans]

Currently this splits resetStore into two steps: clearStore and reFetchObservableQueries. The reason to do this is to have the onResetStore callbacks run when the store is empty.

The problem with this split as a simple implementation is this error is used to reject the in-flight queries. When the promise representing the in-flight query is rejected, this code path for notifying the observableQuery of an error is invoked. If the query is not told to be refetched before that code, then a check for a new request fails. The in-flight error is then passed to the observableQuery, which notifies the observableQuery of the error.

The current implementation of apollo-client invokes getObservableQueryPromises, refetching all observable queries, in the same function/event step as the in-flight error rejection, so on the next promise step when the catch call for the in-flight error runs and sees that another query is in-flight, so it does not notify the observableQuery of the error.

The question then is how should clearStore behave. There are two options after clearing the store: refetch the observableQueries after the store is cleared and return promises representing the result of these fetches OR simply suspend the observableQueries, preventing them from notifying.

I think clearStore should not start the observableQuery refetch, since there would be a race condition between when finish their fetch and the onResetStore callbacks. This means that we need to have a way of suspending the observableQueries. These changes increase the lastRequestId in order to prevent the in-flight error from notifying, essentially simulating that a refetch is occurring without actually refetching. The other option is to create a networkStatus that pauses the observableQuery notification.

Another thing to note is the promise representing the fetch is garbage collected after the error has notified, so an other option of not erroring on an observableQuery when the store is reset would need to take that into account

[peggyrayzis]

Thank you @akiran, @evans, and @jbaxleyiii for all your work on this PR!! So excited to finally squash this bug