Revert of Moved ambient lights out of SkLight's light array

gm/shadowmaps.cpp

Index: gm/shadowmaps.cpp
diff --git a/gm/shadowmaps.cpp b/gm/shadowmaps.cpp
index d8682ce44fbde78a1abf0ecb8bd0ba231da360ac..6c9738b2478ed70446ca461f5c364b257ab1dc84 100644
--- a/gm/shadowmaps.cpp
+++ b/gm/shadowmaps.cpp
@@ -74,7 +74,7 @@
                                                      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.setAmbientLightColor(SkColor3f::Make(0.4f, 0.4f, 0.4f));
+        builder.add(SkLights::Light::MakeAmbient(SkColor3f::Make(0.4f, 0.4f, 0.4f)));
         fLights = builder.finish();
 
         fShadowParams.fShadowRadius = 4.0f;