[wasm] Do not try start linking if the compilation failed.

src/wasm/wasm-module.cc

Index: src/wasm/wasm-module.cc
diff --git a/src/wasm/wasm-module.cc b/src/wasm/wasm-module.cc
index 9e3f0a98e0d5df1f31b39bf73e30b469f653fbce..89bc5b7f032c3c4f53dd7160168ac67d2715d8e8 100644
--- a/src/wasm/wasm-module.cc
+++ b/src/wasm/wasm-module.cc
@@ -774,6 +774,7 @@ MaybeHandle<JSObject> WasmModule::Instantiate(
     if (!FinishCompilation(isolate, this, ffi, results, instance, code_table,
                            thrower, factory, module_env, code_stats, desc)) {
       instance.js_object = Handle<JSObject>::null();
+      return instance.js_object;
     }
 
     // Patch all direct call sites.