TURBOPACK: add runtime js chunk load fallback

turbopack/crates/turbopack-ecmascript-runtime/js/src/browser/runtime/dom/runtime-backend-dom.ts

@@ -141,12 +141,33 @@ const chunkResolvers: Map<ChunkUrl, ChunkResolver> = new Map()
       return resolver.promise
     }
 
-    if (sourceType === SourceType.Runtime && isCss(chunkUrl)) {
+    if (sourceType === SourceType.Runtime) {
       // CSS chunks do not register themselves, and as such must be marked as
       // loaded instantly.
       resolver.loadingStarted = true
-      resolver.resolve()
-      return resolver.promise
+
+      if (isCss(chunkUrl)) {
+        resolver.resolve()
+        return resolver.promise
+      }
+
+      // Runtime JS chunks are expected to be present in the DOM already.
+      // Load it first
+      if (typeof importScripts !== 'function') {
+        const decodedChunkUrl = decodeURI(chunkUrl)
+        const previousScripts = document.querySelectorAll(
+          `script[src="${chunkUrl}"],script[src^="${chunkUrl}?"],script[src="${decodedChunkUrl}"],script[src^="${decodedChunkUrl}?"]`
+        )
+        if (previousScripts.length > 0) {
+          for (const script of Array.from(previousScripts)) {
+            script.addEventListener('error', () => {
+              resolver.reject()
+            })
+          }
+          return resolver.promise
+        }
+      }
+      // If it wasn't present in the DOM, fallback to loading logic.
     }
 
     if (typeof importScripts === 'function') {