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

src/utils/SkShadowPaintFilterCanvas.cpp

Index: src/utils/SkShadowPaintFilterCanvas.cpp
diff --git a/src/utils/SkShadowPaintFilterCanvas.cpp b/src/utils/SkShadowPaintFilterCanvas.cpp
index ef29c3709d95ba7a45c413aa922544ed2d5ff971..e4308709edf49ed0bd7f1c4734f0a0c1b8abfc54 100644
--- a/src/utils/SkShadowPaintFilterCanvas.cpp
+++ b/src/utils/SkShadowPaintFilterCanvas.cpp
@@ -50,6 +50,7 @@
 
 SkISize SkShadowPaintFilterCanvas::ComputeDepthMapSize(const SkLights::Light& light, int maxDepth,
                                                        int width, int height) {
+    SkASSERT(light.type() != SkLights::Light::kAmbient_LightType);
     if (light.type() != SkLights::Light::kDirectional_LightType) {
         return SkISize::Make(width *2 , height * 2);
     }