Promote elevated lines properties to stable: line-z-offset and line-elevation-reference (internal-9756)

GitOrigin-RevId: 9bfbd8e6d1d80e0787c4015b19537e3379cc0bc1

Author: lasselammi

src/style-spec/reference/v8.json

@@ -2701,8 +2701,7 @@
     },
     "line-z-offset": {
       "type": "number",
-      "experimental": true,
-      "doc": "Vertical offset from ground, in meters. Defaults to 0. This is an experimental property with some known issues:\n * Not supported for globe projection at the moment \n * Elevated line discontinuity is possible on tile borders with terrain enabled \n * Rendering artifacts can happen near line joins and line caps depending on the line styling \n * Rendering artifacts relating to `line-opacity` and `line-blur` \n * Elevated line visibility is determined by layer order \n * Z-fighting issues can happen with intersecting elevated lines \n * Elevated lines don't cast shadows",
+      "doc": "Vertical offset from ground, in meters. Not supported for globe projection at the moment.",
       "default": 0,
       "requires": [
         "line-elevation-reference"
@@ -2747,7 +2746,6 @@
         }
       },
       "default": "none",
-      "experimental": true,
       "transition": false,
       "sdk-support": {
         "basic functionality": {

src/style-spec/types.ts

@@ -700,13 +700,7 @@ export type LineLayerSpecification = {
         "line-miter-limit"?: PropertyValueSpecification<number>,
         "line-round-limit"?: PropertyValueSpecification<number>,
         "line-sort-key"?: DataDrivenPropertyValueSpecification<number>,
-        /**
-         * @experimental This property is experimental and subject to change in future versions.
-         */
         "line-z-offset"?: DataDrivenPropertyValueSpecification<number>,
-        /**
-         * @experimental This property is experimental and subject to change in future versions.
-         */
         "line-elevation-reference"?: "none" | "sea" | "ground" | "hd-road-markup" | ExpressionSpecification,
         /**
          * @experimental This property is experimental and subject to change in future versions.