Promisify emscripten modules & fix webp examples (#817)

src/codecs/util.ts

@@ -1,28 +1,19 @@
 type ModuleFactory<M extends EmscriptenWasm.Module> = (
   opts: EmscriptenWasm.ModuleOpts,
-) => M;
+) => Promise<M>;
 
 export function initEmscriptenModule<T extends EmscriptenWasm.Module>(
   moduleFactory: ModuleFactory<T>,
   wasmUrl: string,
 ): Promise<T> {
-  return new Promise((resolve) => {
-    const module = moduleFactory({
-      // Just to be safe, don't automatically invoke any wasm functions
-      noInitialRun: true,
-      locateFile(url: string): string {
-        // Redirect the request for the wasm binary to whatever webpack gave us.
-        if (url.endsWith('.wasm')) return wasmUrl;
-        return url;
-      },
-      onRuntimeInitialized() {
-        // An Emscripten is a then-able that resolves with itself, causing an infite loop when you
-        // wrap it in a real promise. Delete the `then` prop solves this for now.
-        // https://github.com/kripken/emscripten/issues/5820
-        delete (module as any).then;
-        resolve(module);
-      },
-    });
+  return moduleFactory({
+    // Just to be safe, don't automatically invoke any wasm functions
+    noInitialRun: true,
+    locateFile(url: string): string {
+      // Redirect the request for the wasm binary to whatever webpack gave us.
+      if (url.endsWith('.wasm')) return wasmUrl;
+      return url;
+    },
   });
 }