Use boolean type for Directional light cast-shadows property (internal-1831)

Author: stepankuzmin

src/style-spec/reference/v8.json

@@ -483,9 +483,6 @@
       "default": false,
       "doc": "Enable/Disable shadow casting for this light",
       "transition": false,
-      "expression": {
-        "interpolated": false
-      },
       "property-type": "data-constant",
       "sdk-support": {
         "basic functionality": {

src/style-spec/types.ts

@@ -347,7 +347,7 @@ export type DirectionalLightSpecification = {
         "color-transition"?: TransitionSpecification,
         "intensity"?: PropertyValueSpecification<number>,
         "intensity-transition"?: TransitionSpecification,
-        "cast-shadows"?: ExpressionSpecification,
+        "cast-shadows"?: boolean,
         "shadow-intensity"?: PropertyValueSpecification<number>,
         "shadow-intensity-transition"?: TransitionSpecification
     },

test/build/typings/index.ts

@@ -394,6 +394,20 @@ map.setTerrain({'source': 'mapbox-dem', 'exaggeration': 1.5});
 map.setTerrain(undefined);
 map.setTerrain(null);
 
+//
+// 3D Lights
+//
+
+map.setLights([
+    {
+        "id": "directional",
+        "type": "directional",
+        "properties": {
+            "cast-shadows": true,
+        }
+    }
+]);
+
 //
 // Query features
 //