rename some flattenable routines

Initialize felt a little too nebulous, and I think
the verb for "define registrar entry" is "register".

Change-Id: I52f2eb5df5acd46a8b38bb9ea9bb07f4ac8f3789
Reviewed-on: https://skia-review.googlesource.com/c/163990
Commit-Queue: Mike Klein <mtklein@google.com>
Reviewed-by: Mike Klein <mtklein@google.com>
diff --git a/src/effects/SkHighContrastFilter.cpp b/src/effects/SkHighContrastFilter.cpp
index 9c02429..ed5ba19 100644
--- a/src/effects/SkHighContrastFilter.cpp
+++ b/src/effects/SkHighContrastFilter.cpp
@@ -151,8 +151,8 @@
     return sk_make_sp<SkHighContrast_Filter>(config);
 }
 
-void SkHighContrastFilter::InitializeFlattenables() {
-    SK_DEFINE_FLATTENABLE_REGISTRAR_ENTRY(SkHighContrast_Filter)
+void SkHighContrastFilter::RegisterFlattenables() {
+    SK_REGISTER_FLATTENABLE(SkHighContrast_Filter)
 }
 
 #if SK_SUPPORT_GPU