Electronic horizon position notification should directly contain pointer to edge tree

[1ec5]

As of #2834, the electronicHorizonDidUpdatePosition notification’s user info dictionary’s treeKey is set to an instance of the ElectronicHorizon struct, whose only purpose is to hold the starting ElectronicHorizon.Edge of the tree. This is redundant. Assuming we don’t intend to add more properties to MapboxNavigationNative.ElectronicHorizon in the future, we should eliminate the struct and place the starting edge directly in the user info dictionary. The extensive struct documentation comment should be split between ElectronicHorizon.Edge, ElectronicHorizonOptions, and treeKey. Nested types like ElectronicHorizon.Edge should be renamed to no longer nest underneath ElectronicHorizon.

/ref #2834 (comment)
/cc @mapbox/navigation-ios

[1ec5]

Assuming we don’t intend to add more properties to MapboxNavigationNative.ElectronicHorizon in the future

@mapbox/navnative is this a reasonable assumption? Are there any other reasons for the indirection around the ElectronicHorizon type?

[SiarheiFedartsou]

Assuming we don’t intend to add more properties to MapboxNavigationNative.ElectronicHorizon in the future

@mapbox/navnative is this a reasonable assumption? Are there any other reasons for the indirection around the ElectronicHorizon type?

The main idea why we don't send ElectronicHorizonEdge directly, but have this ElectronicHorizon is that we potentially may add some fields to ElectronicHorizon itself, which may be helpful for end user. Tbh I don't have examples of those, but who knows? :)

[1ec5]

The main idea why we don't send ElectronicHorizonEdge directly, but have this ElectronicHorizon is that we potentially may add some fields to ElectronicHorizon itself, which may be helpful for end user. Tbh I don't have examples of those, but who knows? :)

Most likely we’d add any such fields to the notification itself rather than a separate ElectronicHorizon type, but if necessary we do have the flexibility to put an object of a different type in the notification, because notifications aren’t strongly typed.

[azarovalex]

PR merged.