Add tabs to hide/show data views.

All files with data views are shown by default. Click the chevron in the
top left of the view to expand/collapse the data view.

Bug: b/197626844

Test: upload or run a trace to the x20 staging version linked on the
bug.

Change-Id: I8fdd222e3299670285466fe97f958caa537a1f7e
2 files changed