[skottie] Fix OOB access in Parse<SkPoint>

SkJSON requires valid array indices, so callers must guard against
out-of-bounds conditions explicitly.

Bug: oss-fuzz:8956
Change-Id: I50b96b088e44a4c1a569e6911d4be5d75799b464
Reviewed-on: https://skia-review.googlesource.com/135445
Commit-Queue: Florin Malita <fmalita@chromium.org>
Reviewed-by: Kevin Lubick <kjlubick@google.com>
diff --git a/BUILD.gn b/BUILD.gn
index 2a832a5..1691936 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -1385,6 +1385,7 @@
       ":flags",
       ":skia",
       ":tool_utils",
+      "modules/skottie:tests",
       "modules/sksg:tests",
       "//third_party/libpng",
       "//third_party/zlib",