remove align16 calls in skhader context sizes. will handle this elsewhere as needed

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1768433003

TBR=

basically reverts previous CL, but keeps the create --> onCreate change

Review URL: https://codereview.chromium.org/1768433003
diff --git a/experimental/SkPerlinNoiseShader2/SkPerlinNoiseShader2.cpp b/experimental/SkPerlinNoiseShader2/SkPerlinNoiseShader2.cpp
index a1784a4..9e839f1 100644
--- a/experimental/SkPerlinNoiseShader2/SkPerlinNoiseShader2.cpp
+++ b/experimental/SkPerlinNoiseShader2/SkPerlinNoiseShader2.cpp
@@ -572,7 +572,7 @@
 }
 
 size_t SkPerlinNoiseShader2::onContextSize(const ContextRec&) const {
-    return SkAlign16(sizeof(PerlinNoiseShaderContext));
+    return sizeof(PerlinNoiseShaderContext);
 }
 
 SkPerlinNoiseShader2::PerlinNoiseShaderContext::PerlinNoiseShaderContext(