Added API for Bevel NormalSource.

src/core/SkLightingShader.cpp

Index: src/core/SkLightingShader.cpp
diff --git a/src/core/SkLightingShader.cpp b/src/core/SkLightingShader.cpp
index 02f14b34ddc9215c72070aeedc769a8f36418cd2..c393dc8c02922f4aeb3982e669d20fb4bd13cb7a 100644
--- a/src/core/SkLightingShader.cpp
+++ b/src/core/SkLightingShader.cpp
@@ -491,12 +491,13 @@ SkShader::Context* SkLightingShaderImpl::onCreateContext(const ContextRec& rec,
 sk_sp<SkShader> SkLightingShader::Make(sk_sp<SkShader> diffuseShader,
                                        sk_sp<SkNormalSource> normalSource,
                                        sk_sp<SkLights> lights) {
-    if (!diffuseShader || !normalSource) {
+    if (!diffuseShader) {
         // TODO: Use paint's color in absence of a diffuseShader
-        // TODO: Use a default implementation of normalSource instead
         return nullptr;
     }

[robertphillips, 2016/07/11 19:13:21]

Hmmm, don't we just want the flat guy?

[dvonbeck, 2016/07/13 14:23:37]

This was before i wrote the flat guy. Now that I uploaded the rebase the flat
guy is used here.

[robertphillips, 2016/07/13 14:40:22]

This doesn't look like the flat guy. 

[dvonbeck, 2016/07/13 16:09:16]

Patch 5 no longer has modifications to lighting shader. Once this CL is landed
(after the nullptr CL lands) it will not modify SkLightingShader.cpp, so the
Make function will continue using the flat guy.

-
+    if (!normalSource) {
+        normalSource = SkNormalSource::MakeBevel(SkNormalSource::BevelType::kLinear, 0, 0);
+    }
     return sk_make_sp<SkLightingShaderImpl>(std::move(diffuseShader), std::move(normalSource),
                                             std::move(lights));
 }