Lazily compute boundfunction .name and .length if possible

src/objects.h

Index: src/objects.h
diff --git a/src/objects.h b/src/objects.h
index 2d0f9ea868e1cdba219dd606a2bb093344b09a20..cccbbe2896b1f6de3aa77e491735b77c200c439c 100644
--- a/src/objects.h
+++ b/src/objects.h
@@ -7382,12 +7382,6 @@ class JSModule: public JSObject {
 // JSBoundFunction describes a bound function exotic object.
 class JSBoundFunction : public JSObject {
  public:
-  // [length]: The bound function "length" property.
-  DECL_ACCESSORS(length, Object)
-
-  // [name]: The bound function "name" property.
-  DECL_ACCESSORS(name, Object)
-
   // [bound_target_function]: The wrapped function object.
   DECL_ACCESSORS(bound_target_function, JSReceiver)
 
@@ -7399,6 +7393,8 @@ class JSBoundFunction : public JSObject {
   // arguments to any call to the wrapped function.
   DECL_ACCESSORS(bound_arguments, FixedArray)
 
+  static MaybeHandle<String> GetName(Isolate* isolate,
+                                     Handle<JSBoundFunction> function);
   static MaybeHandle<Context> GetFunctionRealm(
       Handle<JSBoundFunction> function);
 
@@ -7416,13 +7412,7 @@ class JSBoundFunction : public JSObject {
   static const int kBoundTargetFunctionOffset = JSObject::kHeaderSize;
   static const int kBoundThisOffset = kBoundTargetFunctionOffset + kPointerSize;
   static const int kBoundArgumentsOffset = kBoundThisOffset + kPointerSize;
-  static const int kLengthOffset = kBoundArgumentsOffset + kPointerSize;
-  static const int kNameOffset = kLengthOffset + kPointerSize;
-  static const int kSize = kNameOffset + kPointerSize;
-
-  // Indices of in-object properties.
-  static const int kLengthIndex = 0;
-  static const int kNameIndex = 1;
+  static const int kSize = kBoundArgumentsOffset + kPointerSize;
 
  private:
   DISALLOW_IMPLICIT_CONSTRUCTORS(JSBoundFunction);
@@ -7445,6 +7435,9 @@ class JSFunction: public JSObject {
   inline JSObject* global_proxy();
   inline Context* native_context();
 
+  static Handle<Object> GetName(Isolate* isolate, Handle<JSFunction> function);
+  static MaybeHandle<Smi> GetLength(Isolate* isolate,
+                                    Handle<JSFunction> function);
   static Handle<Context> GetFunctionRealm(Handle<JSFunction> function);
 
   // [code]: The generated code object for this function.  Executed