bindings: Support Web IDL async iterable (3.1 of 4)

Moves the iterator kind from AsyncIteratorBase to IterationSourceBase
following the suggestion at https://crrev.com/c/4685044 .

Bug: 1087157
Change-Id: I0c50ef7b9daa3a7ea93581a48b3c1a41e78a7dd5
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4805732
Reviewed-by: Raphael Kubo Da Costa <raphael.kubo.da.costa@intel.com>
Commit-Queue: Yuki Shiino <yukishiino@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1187664}

third_party/blink/renderer/bindings/scripts/bind_gen/async_iterator.py

@@ -30,11 +30,11 @@ def make_constructors(cg_context):
 
     decls = ListNode([
         CxxFuncDefNode(name=cg_context.class_name,
-                       arg_decls=["IterationSourceBase* source", "Kind kind"],
+                       arg_decls=["IterationSourceBase* source"],
                        return_type="",
                        explicit=True,
                        member_initializer_list=[
-                           "${base_class_name}(source, kind)",
+                           "${base_class_name}(source)",
                        ]),
         CxxFuncDeclNode(name="~AsyncIterator",
                         arg_decls=[],

third_party/blink/renderer/platform/bindings/async_iterator_base.cc

@@ -9,14 +9,14 @@ namespace blink::bindings {
 v8::Local<v8::Promise> AsyncIteratorBase::next(
     ScriptState* script_state,
     ExceptionState& exception_state) {
-  return iteration_source_->Next(script_state, kind_, exception_state);
+  return iteration_source_->Next(script_state, exception_state);
 }
 
 v8::Local<v8::Promise> AsyncIteratorBase::returnForBinding(
     ScriptState* script_state,
     v8::Local<v8::Value> value,
     ExceptionState& exception_state) {
-  return iteration_source_->Return(script_state, kind_, value, exception_state);
+  return iteration_source_->Return(script_state, value, exception_state);
 }
 
 void AsyncIteratorBase::Trace(Visitor* visitor) const {

third_party/blink/renderer/platform/bindings/async_iterator_base.h

@@ -21,31 +21,34 @@ namespace bindings {
 // implementation of async iterators.
 class PLATFORM_EXPORT AsyncIteratorBase : public ScriptWrappable {
  public:
-  // https://webidl.spec.whatwg.org/#default-asynchronous-iterator-object-kind
-  enum class Kind {
-    kKey,
-    kValue,
-    kKeyValue,
-  };
-
   class PLATFORM_EXPORT IterationSourceBase
       : public GarbageCollected<IterationSourceBase> {
    public:
-    IterationSourceBase() = default;
+    // https://webidl.spec.whatwg.org/#default-asynchronous-iterator-object-kind
+    enum class Kind {
+      kKey,
+      kValue,
+      kKeyValue,
+    };
+
+    explicit IterationSourceBase(Kind kind) : kind_(kind) {}
     virtual ~IterationSourceBase() = default;
     IterationSourceBase(const IterationSourceBase&) = delete;
     IterationSourceBase& operator=(const IterationSourceBase&) = delete;
 
     virtual v8::Local<v8::Promise> Next(ScriptState* script_state,
-                                        Kind kind,
                                         ExceptionState& exception_state) = 0;
 
     virtual v8::Local<v8::Promise> Return(ScriptState* script_state,
-                                          Kind kind,
                                           v8::Local<v8::Value> value,
                                           ExceptionState& exception_state) = 0;
 
+    Kind GetKind() const { return kind_; }
+
     virtual void Trace(Visitor* visitor) const {}
+
+   private:
+    const Kind kind_;
   };
 
   ~AsyncIteratorBase() override = default;
@@ -60,11 +63,10 @@ class PLATFORM_EXPORT AsyncIteratorBase : public ScriptWrappable {
   void Trace(Visitor* visitor) const override;
 
  protected:
-  explicit AsyncIteratorBase(IterationSourceBase* iteration_source, Kind kind)
-      : iteration_source_(iteration_source), kind_(kind) {}
+  explicit AsyncIteratorBase(IterationSourceBase* iteration_source)
+      : iteration_source_(iteration_source) {}
 
   const Member<IterationSourceBase> iteration_source_;
-  const Kind kind_;
 };
 
 }  // namespace bindings