Fix PlaceAutocompleteAdapter data modification from background thread

[nikson]

Filter (protected FilterResults performFiltering()) is modifying the data in background, it crashed when getItem() is accessed from UI-thread. Following error also generate when publishResults invoked.

Fatal Exception: java.lang.IllegalStateException: The content of the adapter has changed but ListView did not receive a notification. Make sure the content of your adapter is not modified from a background thread, but only from the UI thread. Make sure your adapter calls notifyDataSetChanged() when its content changes. [in ListView(-1, class android.widget.ListPopupWindow$DropDownListView) with Adapter

The sample code is not correct and it rise these (#23, #27) expected issues when integrate in application.

Fix #27, #23

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[googlebot]

CLAs look good, thanks!

[nikson]

Hi @jfschmakeit, can you please have a look at this issue?

[edumucelli]

Wow, this fix a nasty bug I had when using this PlaceAutoCompleteAdapter! Thanks @nikson

[kanetik]

Is anyone maintaining this repo? There's 4 open PRs here, this one being a HUGE fix that absolutely needs to be merged in.

[stephenmcd]

Thanks @nikson