Set correct divider dimension for task menu options

Previously divider drawable dimension was set on height,
which only works when things are divided vertically.
For horizontal layouts, we need to set divider width.

Bug: 192398954
Test: Tested portrait + fake/real landscape
+ tablet

Change-Id: I5a63df9749bf37c3a563e923a1b4724aa17d9409
6 files changed