Rewrite SkTRegistry to take any trivially-copyable type.

samplecode/SampleApp.cpp

Index: samplecode/SampleApp.cpp
diff --git a/samplecode/SampleApp.cpp b/samplecode/SampleApp.cpp
index b3632f840ff0d7e8f6473bcb9adfb40faa818422..1942eb29c50b63516b4a17e9b9715467563dd180 100644
--- a/samplecode/SampleApp.cpp
+++ b/samplecode/SampleApp.cpp
@@ -428,7 +428,7 @@ static void SkGMRegistyToSampleRegistry() {
     if (!gOnce) {
         const skiagm::GMRegistry* gmreg = skiagm::GMRegistry::Head();
         while (gmreg) {
-            fRegisters.push_back() = new SkViewRegister(gmreg->factory());
+            fRegisters.push_back() = new SkViewRegister(gmreg->data());
             gmreg = gmreg->next();
         }
         gOnce = true;