Removed submodule maplibre-gl-js (#938)

shaders/fill_outline.vertex.glsl

@@ -0,0 +1,17 @@
+attribute vec2 a_pos;
+
+uniform mat4 u_matrix;
+uniform vec2 u_world;
+
+varying vec2 v_pos;
+
+#pragma mapbox: define highp vec4 outline_color
+#pragma mapbox: define lowp float opacity
+
+void main() {
+    #pragma mapbox: initialize highp vec4 outline_color
+    #pragma mapbox: initialize lowp float opacity
+
+    gl_Position = u_matrix * vec4(a_pos, 0, 1);
+    v_pos = (gl_Position.xy / gl_Position.w + 1.0) / 2.0 * u_world;
+}