[wasm] Add a magic word and a version number to the binary.

test/cctest/wasm/test-run-wasm-module.cc

Index: test/cctest/wasm/test-run-wasm-module.cc
diff --git a/test/cctest/wasm/test-run-wasm-module.cc b/test/cctest/wasm/test-run-wasm-module.cc
index 905e8e493275693a77be403436bd4e0f7ee440bb..32eace1acbe8a1a3898ef51be206cb53fda59ab2 100644
--- a/test/cctest/wasm/test-run-wasm-module.cc
+++ b/test/cctest/wasm/test-run-wasm-module.cc
@@ -36,6 +36,7 @@ void TestModule(WasmModuleIndex* module, int32_t expected_result) {
 // A raw test that skips the WasmModuleBuilder.
 TEST(Run_WasmModule_CallAdd_rev) {
   static const byte data[] = {
+      WASM_MODULE_HEADER,
       // sig#0 ------------------------------------------
       kDeclSignatures, 2, 0, kLocalI32,    // void -> int
       2, kLocalI32, kLocalI32, kLocalI32,  // int,int -> int