[Bindings] Remove redundant ToObject invocation in dictionary toImpl.

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 %}
 
@@ skipping 19 matching lines @@
 
   {% 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 %}
   v8::TryCatch block(isolate);
-  v8::Local<v8::Object> v8Object;
-  if (!v8Call(v8Value->ToObject(isolate->GetCurrentContext()), v8Object, block)) {
-    exceptionState.rethrowV8Exception(block.Exception());
-    return;
-  }
+  v8::Local<v8::Object> v8Object = v8Value.As<v8::Object>();

[Yuki, 2017/03/16 07:10:43]

nit: Could you move this cast up to just after line 29 (just after we checked
v8Value->IsObject())?

   {% 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)) {
     exceptionState.rethrowV8Exception(block.Exception());
     return;
   }
   if ({{member.name}}Value.IsEmpty() || {{member.name}}Value->IsUndefined()) {
     {% if member.is_required %}
@@ skipping 74 matching lines @@
 
 {{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 #}