Supply permission callback

[skywalkerDavid]

Descriptions:

Supply the permission callbacks.

1. Supply the denied and neverAskAgain callback
2. Supply onCheckLocationPermissionResult, since onRequestPermissionsResult in NativeGoogleMapFragment and WebviewMapFragment won't be called when requestPermissions.

Test:

Tested with Sample app

Reviewers:

@felipecsl @gpeal @nwadams

[felipecsl]

Is this the fix for #112?

[skywalkerDavid]

@felipecsl yes, it fixes the #112 and 1 other issue about permission: setMyLocationEnabled won't work immediately even after the permission is accepted.

Thank you for the comments, they are all very good, I will address them soon.

[skywalkerDavid]

Comments addressed.

[skywalkerDavid]

@felipecsl PTAL, thank you