Typo fixes, added line to MGLStyleLayer initializer description

[jmkiley]

• Corrected typos in MGLMapView.h and MGLMapCamera.h
• Removed line from MGLShapeCollection.h
• Inserted a reminder in MGLStyleLayer.h initializer description to remind user not to initialize MGLStyleLayer directly

[mention-bot]

@jmkiley, thanks for your PR! By analyzing this pull request, we identified @1ec5, @friedbunny and @incanus to be potential reviewers.

[1ec5]

This sentence was correct except for the inclusion of “multipolyline” instead of “shape collection”.

[1ec5]

This change will get overwritten the next time someone runs make style-code-darwin. This documentation is defined in style-spec-overrides-v8.json.

[1ec5]

Actually, this is the one layer file that isn’t autogenerated, so you can put the additional text directly in here. Sorry for the confusion.

[jmkiley]

Removed the change to MGLStyleLayer.h, edited the line in MGLShapeCollection.h. cc @1ec5

[1ec5]

Did you still want to point this out?

Should not be used to create an instance of MGLStyleLayer directly. Instead, create instances of MGLBackgroundStyleLayer and the concrete subclasses of MGLForegroundStyleLayer.

You can do that in style-spec-overrides-v8.json, then run make style-code-darwin. You should see the line magically reappear in the header as a result.

Regarding this note, I’d say something like the following, so developers know they can use this initializer, just not on MGLStyleLayer itself:

The default implementation of this initializer in MGLStyleLayer creates an invalid style layer. Call this initializer on MGLBackgroundStyleLayer or one of the concrete subclasses of MGLForegroundStyleLayer to create a valid style layer.

[jmkiley]

Inserted the line @1ec5 wrote into the MGLStyleLayer initializer method.