[wasm] Support recompilation if deserialization fails.

include/v8.h

Index: include/v8.h
diff --git a/include/v8.h b/include/v8.h
index 36edf5334a9d27c4cec2ba8238eab8ee808dea8e..9aed9b2b057fcb1d7b04ba53b20f47ab16bfc1d0 100644
--- a/include/v8.h
+++ b/include/v8.h
@@ -3902,13 +3902,23 @@ class V8_EXPORT Proxy : public Object {
 class V8_EXPORT WasmCompiledModule : public Object {
  public:
   typedef std::pair<std::unique_ptr<const uint8_t[]>, size_t> SerializedModule;
+  // Get the uncompiled bytes that were used to compile this module.
+  Local<String> GetUncompiledBytes();
 
+  // Serialize the compiled module. The serialized data does not include the
+  // uncompiled bytes.
   SerializedModule Serialize();
-  static MaybeLocal<WasmCompiledModule> Deserialize(
-      Isolate* isolate, const SerializedModule& serialized_data);

[vogelheim, 2016/10/06 10:00:50]

This is an incompatible API change, and one of the bots is complaining that
Blink won't build. You'll briefly have to support both old + new API.

+
+  // If possible, deserialize the module, otherwise compile it from the provided
+  // uncompiled bytes.
+  static MaybeLocal<WasmCompiledModule> DeserializeOrCompile(
+      Isolate* isolate, const SerializedModule& serialized_data,
+      Local<String> uncompiled_bytes);
   V8_INLINE static WasmCompiledModule* Cast(Value* obj);
 
  private:
+  static MaybeLocal<WasmCompiledModule> Compile(Isolate* isolate,
+                                                Local<String> bytes);
   WasmCompiledModule();
   static void CheckCast(Value* obj);
 };