[darwin] Simplify MGLStyleLayer initialization and pointer management

Similarly to the previous commit, introduce `-[MGLStyleLayer initWithPendingLayer:]`, allowing the base class to track the owned `_pendingSource` pointer and implement `-addToMapView:` and `-removeFromMapView:` without any casts.

Fixes an issue where `-[MGLStyle layerFromMBGLLayer:]` would wind up creating layers whose `_rawLayer` and `_pendingLayer` held different values.

1 files changed, 1 insertions, 17 deletions

diff --git a/platform/darwin/src/MGLForegroundStyleLayer.h b/platform/darwin/src/MGLForegroundStyleLayer.h
index 87763f4634..16a973630e 100644
--- a/platform/darwin/src/MGLForegroundStyleLayer.h
+++ b/platform/darwin/src/MGLForegroundStyleLayer.h
@@ -20,23 +20,7 @@ MGL_EXPORT
 
 #pragma mark Initializing a Style Layer
 
-- (instancetype)init __attribute__((unavailable("Use -initWithIdentifier:source: instead.")));
-- (instancetype)initWithIdentifier:(NSString *)identifier __attribute__((unavailable("Use -initWithIdentifier:source: instead.")));
-
-/**
- Returns a foreground style layer initialized with an identifier and source.
-
- After initializing and configuring the style layer, add it to a map view’s
- style using the `-[MGLStyle addLayer:]` or
- `-[MGLStyle insertLayer:belowLayer:]` method.
-
- @param identifier A string that uniquely identifies the source in the style to
-    which it is added.
- @param source The source from which to obtain the data to style. If the source
-    has not yet been added to the current style, the behavior is undefined.
- @return An initialized foreground style layer.
- */
-- (instancetype)initWithIdentifier:(NSString *)identifier source:(MGLSource *)source NS_DESIGNATED_INITIALIZER;
+- (instancetype)init __attribute__((unavailable("Use -init methods of concrete subclasses instead.")));
 
 #pragma mark Specifying a Style Layer’s Content