Ensure ZILB encoder handles all typed data lists correctly

runtime/bin/filter.cc

Index: runtime/bin/filter.cc
diff --git a/runtime/bin/filter.cc b/runtime/bin/filter.cc
index f537606609fb41a3a270e1358dde709ba0ff28a4..5e87f62a599d6f17d4727760511fba1cb19f04e0 100644
--- a/runtime/bin/filter.cc
+++ b/runtime/bin/filter.cc
@@ -154,7 +154,14 @@ void FUNCTION_NAME(Filter_Process)(Dart_NativeArguments args) {
   uint8_t* buffer = NULL;
   Dart_Handle result = Dart_TypedDataAcquireData(
       data_obj, &type, reinterpret_cast<void**>(&buffer), &length);
+
   if (!Dart_IsError(result)) {
+    ASSERT(type == Dart_TypedData_kUint8 || type == Dart_TypedData_kInt8);
+    if (type != Dart_TypedData_kUint8 && type != Dart_TypedData_kInt8) {
+      Dart_TypedDataReleaseData(data_obj);
+      Dart_ThrowException(DartUtils::NewInternalError(
+          "Invalid argument passed to Filter_Process"));
+    }
     uint8_t* zlib_buffer = new uint8_t[chunk_length];
     if (zlib_buffer == NULL) {
       Dart_TypedDataReleaseData(data_obj);