[modules] Give Module an internal [hash] field

src/objects.h

Index: src/objects.h
diff --git a/src/objects.h b/src/objects.h
index 927c6c7f46183a1e27932d206b3ddb53ca929edf..213e8850fd8a16d808cfe5be7e4c22b1d343faea 100644
--- a/src/objects.h
+++ b/src/objects.h
@@ -7926,15 +7926,15 @@ class Module : public Struct {
   // Embedder-specified data
   DECL_ACCESSORS(embedder_data, Object)
 
+  // Hash for this object (a random non-zero Smi).
+  DECL_INT_ACCESSORS(hash)
+
   // Get the SharedFunctionInfo associated with the code.
   inline SharedFunctionInfo* shared() const;
 
   // Get the ModuleInfo associated with the code.
   inline ModuleInfo* info() const;
 
-  // Compute a hash for this object.
-  inline uint32_t Hash() const;
-
   // Implementation of spec operation ModuleDeclarationInstantiation.
   // Returns false if an exception occurred during instantiation, true
   // otherwise.
@@ -7964,7 +7964,8 @@ class Module : public Struct {
   static const int kFlagsOffset = kRequestedModulesOffset + kPointerSize;
   static const int kEmbedderDataOffset = kFlagsOffset + kPointerSize;
   static const int kModuleNamespaceOffset = kEmbedderDataOffset + kPointerSize;
-  static const int kSize = kModuleNamespaceOffset + kPointerSize;
+  static const int kHashOffset = kModuleNamespaceOffset + kPointerSize;
+  static const int kSize = kHashOffset + kPointerSize;
 
  private:
   enum { kEvaluatedBit };