Added PointLights to SkLights::Light

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2237493002

Review-Url: https://codereview.chromium.org/2237493002
diff --git a/gm/shadowmaps.cpp b/gm/shadowmaps.cpp
index b343d9b..f953550 100644
--- a/gm/shadowmaps.cpp
+++ b/gm/shadowmaps.cpp
@@ -70,11 +70,11 @@
         //   - soft white ambient light
 
         SkLights::Builder builder;
-        builder.add(SkLights::Light(SkColor3f::Make(0.2f, 0.3f, 0.4f),
-                                    SkVector3::Make(0.2f, 0.1f, 1.0f)));
-        builder.add(SkLights::Light(SkColor3f::Make(0.4f, 0.3f, 0.2f),
-                                    SkVector3::Make(0.1f, 0.2f, 1.0f)));
-        builder.add(SkLights::Light(SkColor3f::Make(0.4f, 0.4f, 0.4f)));
+        builder.add(SkLights::Light::MakeDirectional(SkColor3f::Make(0.2f, 0.3f, 0.4f),
+                                                     SkVector3::Make(0.2f, 0.1f, 1.0f)));
+        builder.add(SkLights::Light::MakeDirectional(SkColor3f::Make(0.4f, 0.3f, 0.2f),
+                                                     SkVector3::Make(0.1f, 0.2f, 1.0f)));
+        builder.add(SkLights::Light::MakeAmbient(SkColor3f::Make(0.4f, 0.4f, 0.4f)));
         fLights = builder.finish();
     }