bind-gen: Implement a binary size reduction hack of [Reflect]

Implements/ports tkent[1]'s binary size optimization of
[CEReafctions, Reflect] attribute set callback in the new
binding generator.

The APK size reduces by about 52 KB.

[1] https://crrev.com/c/1732676

Bug: 839389
Change-Id: If485747158ffb4307d5f20e21a1aba807af45ba1
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2291820
Commit-Queue: Yuki Shiino <yukishiino@chromium.org>
Reviewed-by: Hitoshi Yoshida <peria@chromium.org>
Cr-Commit-Position: refs/heads/master@{#787670}

third_party/blink/renderer/bindings/core/v8/generated_code_helper.cc

@@ -344,6 +344,82 @@ v8::Local<v8::Array> EnumerateIndexedProperties(v8::Isolate* isolate,
   return v8::Array::New(isolate, elements.data(), elements.size());
 }
 
+#if defined(USE_BLINK_V8_BINDING_NEW_IDL_INTERFACE)
+
+template <typename IDLType,
+          typename ArgType,
+          void (Element::*MemFunc)(const QualifiedName&, ArgType)>
+void PerformAttributeSetCEReactionsReflect(
+    const v8::FunctionCallbackInfo<v8::Value>& info,
+    const QualifiedName& content_attribute,
+    const char* interface_name,
+    const char* attribute_name) {
+  v8::Isolate* isolate = info.GetIsolate();
+  ExceptionState exception_state(isolate, ExceptionState::kSetterContext,
+                                 interface_name, attribute_name);
+  if (UNLIKELY(info.Length() < 1)) {
+    exception_state.ThrowTypeError(
+        ExceptionMessages::NotEnoughArguments(1, info.Length()));
+    return;
+  }
+
+  // [Reflect]
+  V0CustomElementProcessingStack::CallbackDeliveryScope v0_custom_element_scope;
+  // [CEReactions]
+  CEReactionsScope ce_reactions_scope;
+
+  Element* blink_receiver = V8Element::ToWrappableUnsafe(info.This());
+  auto&& arg_value = NativeValueTraits<IDLType>::NativeValue(isolate, info[0],
+                                                             exception_state);
+  if (exception_state.HadException())
+    return;
+
+  (blink_receiver->*MemFunc)(content_attribute, arg_value);
+}
+
+void PerformAttributeSetCEReactionsReflectTypeBoolean(
+    const v8::FunctionCallbackInfo<v8::Value>& info,
+    const QualifiedName& content_attribute,
+    const char* interface_name,
+    const char* attribute_name) {
+  PerformAttributeSetCEReactionsReflect<IDLBoolean, bool,
+                                        &Element::SetBooleanAttribute>(
+      info, content_attribute, interface_name, attribute_name);
+}
+
+void PerformAttributeSetCEReactionsReflectTypeString(
+    const v8::FunctionCallbackInfo<v8::Value>& info,
+    const QualifiedName& content_attribute,
+    const char* interface_name,
+    const char* attribute_name) {
+  PerformAttributeSetCEReactionsReflect<IDLStringV2, const AtomicString&,
+                                        &Element::setAttribute>(
+      info, content_attribute, interface_name, attribute_name);
+}
+
+void PerformAttributeSetCEReactionsReflectTypeStringLegacyNullToEmptyString(
+    const v8::FunctionCallbackInfo<v8::Value>& info,
+    const QualifiedName& content_attribute,
+    const char* interface_name,
+    const char* attribute_name) {
+  PerformAttributeSetCEReactionsReflect<IDLStringTreatNullAsEmptyStringV2,
+                                        const AtomicString&,
+                                        &Element::setAttribute>(
+      info, content_attribute, interface_name, attribute_name);
+}
+
+void PerformAttributeSetCEReactionsReflectTypeStringOrNull(
+    const v8::FunctionCallbackInfo<v8::Value>& info,
+    const QualifiedName& content_attribute,
+    const char* interface_name,
+    const char* attribute_name) {
+  PerformAttributeSetCEReactionsReflect<
+      IDLNullable<IDLStringV2>, const AtomicString&, &Element::setAttribute>(
+      info, content_attribute, interface_name, attribute_name);
+}
+
+#endif  // USE_BLINK_V8_BINDING_NEW_IDL_INTERFACE
+
 }  // namespace bindings
 
 }  // namespace blink

third_party/blink/renderer/bindings/core/v8/generated_code_helper.h

@@ -228,6 +228,29 @@ bool ConvertDictionaryMember(v8::Isolate* isolate,
   return true;
 }
 
+// Common implementation to reduce the binary size of attribute set callbacks.
+CORE_EXPORT void PerformAttributeSetCEReactionsReflectTypeBoolean(
+    const v8::FunctionCallbackInfo<v8::Value>& info,
+    const QualifiedName& content_attribute,
+    const char* interface_name,
+    const char* attribute_name);
+CORE_EXPORT void PerformAttributeSetCEReactionsReflectTypeString(
+    const v8::FunctionCallbackInfo<v8::Value>& info,
+    const QualifiedName& content_attribute,
+    const char* interface_name,
+    const char* attribute_name);
+CORE_EXPORT void
+PerformAttributeSetCEReactionsReflectTypeStringLegacyNullToEmptyString(
+    const v8::FunctionCallbackInfo<v8::Value>& info,
+    const QualifiedName& content_attribute,
+    const char* interface_name,
+    const char* attribute_name);
+CORE_EXPORT void PerformAttributeSetCEReactionsReflectTypeStringOrNull(
+    const v8::FunctionCallbackInfo<v8::Value>& info,
+    const QualifiedName& content_attribute,
+    const char* interface_name,
+    const char* attribute_name);
+
 }  // namespace bindings
 
 }  // namespace blink

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

@@ -1729,6 +1729,59 @@ EventListener* event_handler = JSEventHandler::CreateOrNull(
         body.append(TextNode(text))
         return func_def
 
+    # Binary size reduction hack
+    # When the following conditions are met, the implementation is shared.
+    # 1. The attribute is annotated with [CEReactions, Reflect] and not
+    #   annotated with other extended attributes having side effect.
+    # 2. The interface is implementing Element.
+    def optimize_element_cereactions_reflect():
+        has_cereactions = False
+        has_reflect = False
+        for key in ext_attrs.keys():
+            if key == "CEReactions":
+                has_cereactions = True
+            elif key == "Reflect":
+                has_reflect = True
+            elif key in ("Affects", "CustomElementCallbacks", "DeprecateAs",
+                         "Exposed", "LogActivity", "LogAllWorlds", "Measure",
+                         "MeasureAs", "ReflectEmpty", "ReflectInvalid",
+                         "ReflectMissing", "ReflectOnly",
+                         "RuntimeCallStatsCounter", "RuntimeEnabled",
+                         "SecureContext", "URL", "Unscopable"):
+                pass
+            else:
+                return None
+        if not (has_cereactions and has_reflect):
+            return None
+        if not cg_context.interface.does_implement("Element"):
+            return None
+        content_attribute = _make_reflect_content_attribute_key(
+            body, cg_context)
+        idl_type = cg_context.attribute.idl_type.unwrap(typedef=True)
+        if idl_type.is_boolean:
+            func_name = "PerformAttributeSetCEReactionsReflectTypeBoolean"
+        elif idl_type.type_name == "String":
+            func_name = "PerformAttributeSetCEReactionsReflectTypeString"
+        elif idl_type.type_name == "StringTreatNullAs":
+            func_name = ("PerformAttributeSetCEReactionsReflect"
+                         "TypeStringLegacyNullToEmptyString")
+        elif idl_type.type_name == "StringOrNull":
+            func_name = "PerformAttributeSetCEReactionsReflectTypeStringOrNull"
+        else:
+            return None
+        text = _format(
+            "bindings::{func_name}"
+            "(${info}, {content_attribute}, "
+            "${class_like_name}, ${property_name});",
+            func_name=func_name,
+            content_attribute=content_attribute)
+        return TextNode(text)
+
+    node = optimize_element_cereactions_reflect()
+    if node:
+        body.append(node)
+        return func_def
+
     body.extend([
         make_check_receiver(cg_context),
         make_check_argument_length(cg_context),