Uses a finalizer to delete zlib filter resources

runtime/bin/filter_unsupported.cc

Index: runtime/bin/filter_unsupported.cc
diff --git a/runtime/bin/filter_unsupported.cc b/runtime/bin/filter_unsupported.cc
index 1742559b847d0f61e37226b509dc47259b00ba65..f01b3db1ca589a6583c39d4b525c0bee9eebb1f3 100644
--- a/runtime/bin/filter_unsupported.cc
+++ b/runtime/bin/filter_unsupported.cc
@@ -16,9 +16,11 @@ void FUNCTION_NAME(Filter_CreateZLibInflate)(Dart_NativeArguments args) {
         "ZLibInflater and Deflater not supported on this platform"));
 }
 
+
 void FUNCTION_NAME(Filter_CreateZLibDeflate)(Dart_NativeArguments args) {
 }
 
+
 void FUNCTION_NAME(Filter_Process)(Dart_NativeArguments args) {
 }
 
@@ -26,9 +28,5 @@ void FUNCTION_NAME(Filter_Process)(Dart_NativeArguments args) {
 void FUNCTION_NAME(Filter_Processed)(Dart_NativeArguments args) {
 }
 
-
-void FUNCTION_NAME(Filter_End)(Dart_NativeArguments args) {
-}
-
 }  // namespace bin
 }  // namespace dart