Move table export to the anyref pass

Turns out rustwasm#1704 was buggy and ended up never injecting initialization
because the anyref table was never present! This fixes that issue and
this should now be tested on CI to ensure this doesn't regress and
future changes preserve correctness

Author: alexcrichton

crates/cli-support/src/anyref.rs

@@ -44,6 +44,21 @@ pub fn process(module: &mut Module) -> Result<(), Error> {
     }
 
     cfg.run(module)?;
+
+    // Make sure to export the `anyref` table for the JS bindings since it
+    // will need to be initialized. If it doesn't exist though then the
+    // module must not use it, so we skip it.
+    let table = module.tables.iter().find(|t| match t.kind {
+        walrus::TableKind::Anyref(_) => true,
+        _ => false,
+    });
+    let table = match table {
+        Some(t) => t.id(),
+        None => return Ok(()),
+    };
+    module.exports.add("__wbg_anyref_table", table);
+
+    // Clean up now-unused intrinsics and shims and such
     walrus::passes::gc::run(module);
 
     // The GC pass above may end up removing some imported intrinsics. For

crates/cli-support/src/webidl/mod.rs

@@ -624,19 +624,6 @@ impl<'a> Context<'a> {
             return Ok(());
         }
 
-        // Make sure to export the `anyref` table for the JS bindings since it
-        // will need to be initialized. If it doesn't exist though then the
-        // module must not use it, so we skip it.
-        let table = self.module.tables.iter().find(|t| match t.kind {
-            walrus::TableKind::Anyref(_) => true,
-            _ => false,
-        });
-        let table = match table {
-            Some(t) => t.id(),
-            None => return Ok(()),
-        };
-        self.module.exports.add("__wbg_anyref_table", table);
-
         let ty = self.module.types.add(&[], &[]);
         let (import, import_id) =
             self.module