SpeedDialEntries with default numbers now properly show up.

This change includes:
 - fixing an issue where default numbers were being removed when inserting duo
 channels.
 - setting a max height on the disambig dialog scrollview because it was
 causing accessibility issues (and will be needed later).

Test: SpeedDialIntegrationTest, SpeedDialUiItemLoaderTest
PiperOrigin-RevId: 194023169
Change-Id: I4896fb5dbbb99aefd9713c6768ea9c07ca906d6d