[skottie] Switch to SkJSON

Convert to SkJSON APIs and remove RapidJSON dependency.

TBR=
Change-Id: I5b4fd78821a443326e3a5b370748d840b80ef279
Reviewed-on: https://skia-review.googlesource.com/134612
Reviewed-by: Mike Klein <mtklein@google.com>
Commit-Queue: Florin Malita <fmalita@chromium.org>
diff --git a/modules/skjson/src/SkJSONBench.cpp b/modules/skjson/src/SkJSONBench.cpp
index b9c3664..4ef1d6c 100644
--- a/modules/skjson/src/SkJSONBench.cpp
+++ b/modules/skjson/src/SkJSONBench.cpp
@@ -55,7 +55,7 @@
 
 DEF_BENCH( return new JsonBench; )
 
-#if !defined(SK_BUILD_FOR_ANDROID_FRAMEWORK)
+#if (0)
 
 #include "rapidjson/document.h"