[Bindings] Cache handles for dictionary keys on V8PerIsolateData.

third_party/WebKit/Source/bindings/templates/dictionary_v8.cpp.tmpl

 {% filter format_blink_cpp_source_code %}
 
 {% from 'utilities.cpp.tmpl' import declare_enum_validation_variable %}
 {% include 'copyright_block.txt' %}
 #include "{{v8_original_class}}.h"
 
 {% for filename in cpp_includes if filename != '%s.h' % v8_class %}
 #include "{{filename}}"
 {% endfor %}
 
 namespace blink {
 
+{% if members %}
+static const v8::Eternal<v8::Name>* eternal{{v8_class}}Keys(v8::Isolate* isolate) {
+  static const char* const kKeys[] = {
+    {% for member in members %}
+    "{{member.name}}",
+    {% endfor %}
+  };
+  return V8PerIsolateData::from(isolate)->findOrCreateKeys(
+      kKeys, kKeys, WTF_ARRAY_LENGTH(kKeys));
+}
+{% endif %}
+
 {% from 'utilities.cpp.tmpl' import v8_value_to_local_cpp_value %}
 void {{v8_class}}::toImpl(v8::Isolate* isolate, v8::Local<v8::Value> v8Value, {{cpp_class}}& impl, ExceptionState& exceptionState) {
   if (isUndefinedOrNull(v8Value)) {
     {% if required_member_names %}
     exceptionState.throwTypeError("Missing required member(s): {{required_member_names|join(', ')}}.");
     {% endif %}
     return;
   }
   if (!v8Value->IsObject()) {
     {% if use_permissive_dictionary_conversion %}
     // Do nothing.
     return;
     {% else %}
     exceptionState.throwTypeError("cannot convert to dictionary.");
     return;
     {% endif %}
   }
   v8::Local<v8::Object> v8Object = v8Value.As<v8::Object>();
   ALLOW_UNUSED_LOCAL(v8Object);
 
   {% if parent_v8_class %}
   {{parent_v8_class}}::toImpl(isolate, v8Value, impl, exceptionState);
   if (exceptionState.hadException())
     return;
 
   {% endif %}
   {# Declare local variables only when the dictionary has members to avoid unused variable warnings. #}
   {% if members %}
+  const v8::Eternal<v8::Name>* keys = eternal{{v8_class}}Keys(isolate);
   v8::TryCatch block(isolate);
+  v8::Local<v8::Context> context = isolate->GetCurrentContext();
   {% endif %}
   {% for member in members %}
   {% filter runtime_enabled(member.runtime_enabled_feature_name) %}
   v8::Local<v8::Value> {{member.name}}Value;
-  if (!v8Object->Get(isolate->GetCurrentContext(), v8AtomicString(isolate, "{{member.name}}")).ToLocal(&{{member.name}}Value)) {
+  if (!v8Object->Get(context, keys[{{loop.index0}}].Get(isolate)).ToLocal(&{{member.name}}Value)) {
     exceptionState.rethrowV8Exception(block.Exception());
     return;
   }
   if ({{member.name}}Value.IsEmpty() || {{member.name}}Value->IsUndefined()) {
     {% if member.is_required %}
     exceptionState.throwTypeError("required member {{member.name}} is undefined.");
     return;
     {% else %}
     // Do nothing.
     {% endif %}
@@ skipping 35 matching lines @@
     return v8::Undefined(isolate);
   return v8Object;
 }
 
 bool toV8{{cpp_class}}(const {{cpp_class}}& impl, v8::Local<v8::Object> dictionary, v8::Local<v8::Object> creationContext, v8::Isolate* isolate) {
   {% if parent_v8_class %}
   if (!toV8{{parent_cpp_class}}(impl, dictionary, creationContext, isolate))
     return false;
 
   {% endif %}
+  {% if members %}
+  const v8::Eternal<v8::Name>* keys = eternal{{v8_class}}Keys(isolate);
+  v8::Local<v8::Context> context = isolate->GetCurrentContext();
+  {% endif %}
   {% for member in members %}
   if (impl.{{member.has_method_name}}()) {
     {% if member.is_object %}
     DCHECK(impl.{{member.getter_name}}().isObject());
     {% endif %}
-    if (!v8CallBoolean(dictionary->CreateDataProperty(isolate->GetCurrentContext(), v8AtomicString(isolate, "{{member.name}}"), {{member.cpp_value_to_v8_value}})))
+    if (!v8CallBoolean(dictionary->CreateDataProperty(context, keys[{{loop.index0}}].Get(isolate), {{member.cpp_value_to_v8_value}})))
       return false;
   {% if member.v8_default_value %}
   } else {
-    if (!v8CallBoolean(dictionary->CreateDataProperty(isolate->GetCurrentContext(), v8AtomicString(isolate, "{{member.name}}"), {{member.v8_default_value}})))
+    if (!v8CallBoolean(dictionary->CreateDataProperty(context, keys[{{loop.index0}}].Get(isolate), {{member.v8_default_value}})))
       return false;
   {% elif member.is_nullable %}
   } else {
-    if (!v8CallBoolean(dictionary->CreateDataProperty(isolate->GetCurrentContext(), v8AtomicString(isolate, "{{member.name}}"), v8::Null(isolate))))
+    if (!v8CallBoolean(dictionary->CreateDataProperty(context, keys[{{loop.index0}}].Get(isolate), v8::Null(isolate))))
       return false;
   {% elif member.is_required %}
   } else {
     NOTREACHED();
   {% endif %}
   }
 
   {% endfor %}
   return true;
 }
 
 {{cpp_class}} NativeValueTraits<{{cpp_class}}>::nativeValue(v8::Isolate* isolate, v8::Local<v8::Value> value, ExceptionState& exceptionState) {
   {{cpp_class}} impl;
   {{v8_class}}::toImpl(isolate, value, impl, exceptionState);
   return impl;
 }
 
 }  // namespace blink
 
 {% endfilter %}{# format_blink_cpp_source_code #}