[Refactor] Split out directions from WebFocusType

Focus code only cares about how focus is being moved, not the direction.
Spatial navigation code used to reuse this enum to also communicate the
direction of navigation.

In https://crrev.com/d5d79fa304dd23c0216051af79b325d292b93dba we moved
the spatial navigation code out of FocusController. Rather than passing
a "dummy" directional value to the focus controller, this CL creates a
new enum for spatial navigation direction (used only by SpatNav code)
and replaces the focus enum's directional values with a single value for
SpatialNavigation.

Bug: 919158
Change-Id: If092c1464957722dec1cd44be1591d6f8c0a17c9
Reviewed-on: https://chromium-review.googlesource.com/c/1407497
Reviewed-by: Philip Rogers <pdr@chromium.org>
Commit-Queue: David Bokan <bokan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#622247}
7 files changed