Add initial support for anyref as an opaque type (#2294)

Another round of trying to push upstream things from my fork.

This PR only adds support for anyref itself as an opaque type. It does NOT implement the full [reference types proposal](https://github.com/WebAssembly/reference-types/blob/master/proposals/reference-types/Overview.md)--so no table.get/set/grow/etc or ref.null, ref.func, etc.

Figured it was easier to review and merge as we go, especially if I did something fundamentally wrong.

***

I did put it under the `--enable-reference-types` flag as I imagine that even though this PR doesn't complete the full feature set, it probably is the right home. Lmk if not.

I'll also be adding a few github comments to places I want to point out/question.

1 files changed, 2 insertions, 2 deletions

diff --git a/scripts/test/shared.py b/scripts/test/shared.py
index 2440077a8..ad2f44c14 100644
--- a/scripts/test/shared.py
+++ b/scripts/test/shared.py
@@ -313,14 +313,14 @@ class Py2CalledProcessError(subprocess.CalledProcessError):
         self.stderr = stderr
 
 
-def run_process(cmd, check=True, input=None, capture_output=False, *args, **kw):
+def run_process(cmd, check=True, input=None, capture_output=False, decode_output=True, *args, **kw):
     if input and type(input) == str:
         input = bytes(input, 'utf-8')
     if capture_output:
         kw['stdout'] = subprocess.PIPE
         kw['stderr'] = subprocess.PIPE
     ret = subprocess.run(cmd, check=check, input=input, *args, **kw)
-    if ret.stdout is not None:
+    if decode_output and ret.stdout is not None:
         ret.stdout = ret.stdout.decode('utf-8')
     if ret.stderr is not None:
         ret.stderr = ret.stderr.decode('utf-8')