Buggy behavior when an endless button gets resized

[flavioarfaria]

Steps to reproduce

1. Replace android:screenOrientation="portrait" by android:configChanges="orientation|screenSize|smallestScreenSize" at the SignInActivity entry in the AndroidManifest.xml file;
2. Press Sign in button;
3. Rotate the screen while the progress is still running.

Observed behavior

The button is resized to fit the larger screen width in landscape mode and the animation is performed only at the left side of the button, assuming that the button width is the same as before rotation.

Expected behavior

The animation should cover the full button width.

[dmytrodanylyk]

@flavioarfaria thanks for contribution, I will review and merge commit in a few hours!