Simplify FusedLocationProvider Internal Check

[sarahsnow1]

Because LocationEngine#removeRequest disables and re-enables the engine (if there are still remaining requests), we no longer need to check to see if the engine should be disabled in FusedLocationProviderApi#checkAllListenersPendingIntentsAndCallbacks but as @ecgreb pointed out we could as an enhancement call LocationEngine#removeAllRequests when the last client is disconnected "to avoid this issue of needing to explicitly remove all requests before shutting down a client"

[msmollin]

Closing as this repo is no longer maintained.