Moved ambient lights out of SkLight's light array

src/core/SkLightingShader.cpp

Index: src/core/SkLightingShader.cpp
diff --git a/src/core/SkLightingShader.cpp b/src/core/SkLightingShader.cpp
index 8fde8bfd37dedc66a244d323be8d40fa92ce87ef..b788b3c6453c2e7f04157882a9c367cddbfb0055 100644
--- a/src/core/SkLightingShader.cpp
+++ b/src/core/SkLightingShader.cpp
@@ -122,11 +122,9 @@ public:
     LightingFP(sk_sp<GrFragmentProcessor> normalFP, sk_sp<SkLights> lights) {
 
         // fuse all ambient lights into a single one
-        fAmbientColor.set(0.0f, 0.0f, 0.0f);
+        fAmbientColor = lights->ambientLightColor();
         for (int i = 0; i < lights->numLights(); ++i) {
-            if (SkLights::Light::kAmbient_LightType == lights->light(i).type()) {
-                fAmbientColor += lights->light(i).color();
-            } else if (SkLights::Light::kDirectional_LightType == lights->light(i).type()) {
+            if (SkLights::Light::kDirectional_LightType == lights->light(i).type()) {
                 fDirectionalLights.push_back(lights->light(i));
                 // TODO get the handle to the shadow map if there is one
             } else {