Use hasScrollAction in ApnEditPageProviderTest

Instead of assuming a fixed tree structure in testing.

Fix: 369416630
Flag: EXEMPT gradle only
Test: atest ApnEditPageProviderTest
(cherry picked from https://googleplex-android-review.googlesource.com/q/commit:0b530fd405eb95dfedf51bc55bc24bd7d446ead8)
Merged-In: I0a50e7665d9049e089b5a0877f17d1f736ee3332
Change-Id: I0a50e7665d9049e089b5a0877f17d1f736ee3332