[wasm] Properly plumb the origin of the WASM module from asm.js translation.

src/wasm/wasm-module.h

Index: src/wasm/wasm-module.h
diff --git a/src/wasm/wasm-module.h b/src/wasm/wasm-module.h
index a05dd393bc412bcf7c36a94bd26d6de856d85b64..90d0fcca820fa25f1129b14c54d262cb78c8e6e0 100644
--- a/src/wasm/wasm-module.h
+++ b/src/wasm/wasm-module.h
@@ -97,6 +97,8 @@ struct WasmDataSegment {
   bool init;               // true if loaded upon instantiation.
 };
 
+enum ModuleOrigin { kWasmOrigin, kAsmJsOrigin };
+
 // Static representation of a module.
 struct WasmModule {
   static const uint8_t kMinMemSize = 12;  // Minimum memory size = 4kb
@@ -110,6 +112,7 @@ struct WasmModule {
   bool mem_export;            // true if the memory is exported.
   bool mem_external;          // true if the memory is external.
   int start_function_index;   // start function, if any.
+  ModuleOrigin origin;        // origin of the module
 
   std::vector<WasmGlobal>* globals;             // globals in this module.
   std::vector<FunctionSig*>* signatures;        // signatures in this module.
@@ -176,7 +179,7 @@ struct ModuleEnv {
   WasmModule* module;
   WasmModuleInstance* instance;
   WasmLinker* linker;
-  bool asm_js;  // true if the module originated from asm.js.
+  ModuleOrigin origin;
 
   bool IsValidGlobal(uint32_t index) {
     return module && index < module->globals->size();
@@ -211,6 +214,8 @@ struct ModuleEnv {
                                             : 0;
   }
 
+  bool asm_js() { return origin == kAsmJsOrigin; }
+
   Handle<Code> GetFunctionCode(uint32_t index);
   Handle<Code> GetImportCode(uint32_t index);
   Handle<FixedArray> GetFunctionTable();