bind-gen: Update PerformAttributeSetCEReactionsReflect

Ports https://crrev.com/c/2351950 to the new bindings generator.

Bug: 839389
Change-Id: Ia3bab7ba01b527acb550b40a7178563f70edd88d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2352571Reviewed-by: Hitoshi Yoshida <peria@chromium.org>
Commit-Queue: Yuki Shiino <yukishiino@chromium.org>
Cr-Commit-Position: refs/heads/master@{#797573}

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

@@ -395,7 +395,7 @@ void PerformAttributeSetCEReactionsReflectTypeString(
     const QualifiedName& content_attribute,
     const char* interface_name,
     const char* attribute_name) {
-  PerformAttributeSetCEReactionsReflect<IDLStringV2, const AtomicString&,
+  PerformAttributeSetCEReactionsReflect<IDLStringV2, AtomicString,
                                         &Element::setAttribute>(
       info, content_attribute, interface_name, attribute_name);
 }
@@ -406,8 +406,7 @@ void PerformAttributeSetCEReactionsReflectTypeStringLegacyNullToEmptyString(
     const char* interface_name,
     const char* attribute_name) {
   PerformAttributeSetCEReactionsReflect<IDLStringTreatNullAsEmptyStringV2,
-                                        const AtomicString&,
-                                        &Element::setAttribute>(
+                                        AtomicString, &Element::setAttribute>(
       info, content_attribute, interface_name, attribute_name);
 }
 
@@ -416,8 +415,8 @@ void PerformAttributeSetCEReactionsReflectTypeStringOrNull(
     const QualifiedName& content_attribute,
     const char* interface_name,
     const char* attribute_name) {
-  PerformAttributeSetCEReactionsReflect<
-      IDLNullable<IDLStringV2>, const AtomicString&, &Element::setAttribute>(
+  PerformAttributeSetCEReactionsReflect<IDLNullable<IDLStringV2>, AtomicString,
+                                        &Element::setAttribute>(
       info, content_attribute, interface_name, attribute_name);
 }