Replace horizontal ScrollViews with tables in the full widgets picker

Test: Run gnl test, AddWidgetTest
      Run Robolectric tests for widgets
      Manual test video: https://drive.google.com/file/d/1uwCtVNIlC9150kv5eEfILfP5r5M7ARYm/view?usp=sharing

Bug: 179797520
Change-Id: I2f4cdf84338a91b63967879d0c9268c312ace19b
12 files changed