Programmatically set italics rather than using a span

So that the characters that can exceed the view bounds (e.g.
'w') are not cut off

Test: manual
Flag: android.app.nm_summarization_ui
Fixes: 422881504
(cherry picked from https://googleplex-android-review.googlesource.com/q/commit:ef4b2c1c9b0475b68e0b7cbd1464471ed08ebc72)
Merged-In: I19963cfa7a18a39cf44ae021c10b12fd437cc324
Change-Id: I19963cfa7a18a39cf44ae021c10b12fd437cc324