gin: Create a DataObjectBuilder class to help create simple data objects.

extensions/renderer/binding_generating_native_handler.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "extensions/renderer/binding_generating_native_handler.h"
 
 #include "base/macros.h"
 #include "base/metrics/histogram_macros.h"
 #include "base/timer/elapsed_timer.h"
 #include "extensions/renderer/script_context.h"
 #include "extensions/renderer/v8_helpers.h"
+#include "gin/data_object_builder.h"
 
 namespace extensions {
 
 using namespace v8_helpers;
 
 BindingGeneratingNativeHandler::BindingGeneratingNativeHandler(
     ScriptContext* context,
     const std::string& api_name,
     const std::string& bind_to)
     : context_(context), api_name_(api_name), bind_to_(bind_to) {}
 
 v8::Local<v8::Object> BindingGeneratingNativeHandler::NewInstance() {
   base::ElapsedTimer timer;
   // This long sequence of commands effectively runs the JavaScript code,
   // such that result[bind_to] is the compiled schema for |api_name|:
   //
   //   var result = {};
   //   result[bind_to] = require('binding').Binding.create(api_name).generate();
   //   return result;
   //
   // Unfortunately using the v8 APIs makes that quite verbose.
   // Each stage is marked with the code it executes.
   v8::Isolate* isolate = context_->isolate();
   v8::EscapableHandleScope scope(isolate);
 
   // Convert |api_name| and |bind_to| into their v8::Strings to pass
   // through the v8 APIs.
   v8::Local<v8::String> v8_api_name;
-  v8::Local<v8::String> v8_bind_to;
-  if (!ToV8String(isolate, api_name_, &v8_api_name) ||
-      !ToV8String(isolate, bind_to_, &v8_bind_to)) {
+  if (!ToV8String(isolate, api_name_, &v8_api_name)) {
     NOTREACHED();
     return v8::Local<v8::Object>();
   }
 
   v8::Local<v8::Context> v8_context = context_->v8_context();
 
   // require('binding');
   v8::Local<v8::Object> binding_module;
   if (!context_->module_system()->Require("binding").ToLocal(&binding_module)) {
     NOTREACHED();
@@ skipping 34 matching lines @@
   // require('binding').Binding.create(api_name).generate;
   v8::Local<v8::Value> generate_value;
   if (!GetProperty(v8_context, binding_instance, "generate", &generate_value) ||
       !generate_value->IsFunction()) {
     NOTREACHED();
     return v8::Local<v8::Object>();
   }
   v8::Local<v8::Function> generate = generate_value.As<v8::Function>();
 
   // require('binding').Binding.create(api_name).generate();
-  v8::Local<v8::Object> object = v8::Object::New(isolate);
   v8::Local<v8::Value> compiled_schema;
   if (!CallFunction(v8_context, generate, binding_instance, 0, nullptr,
                     &compiled_schema)) {
     NOTREACHED();
     return v8::Local<v8::Object>();
   }
 
   // var result = {};
   // result[bind_to] = ...;
-  if (!SetProperty(v8_context, object, v8_bind_to, compiled_schema)) {
-    NOTREACHED();
-    return v8::Local<v8::Object>();
-  }
+  v8::Local<v8::Object> object =
+      gin::DataObjectBuilder(isolate).Set(bind_to_, compiled_schema).Finish();
 
   // Log UMA with microsecond accuracy*; maxes at 10 seconds.
   // *Obviously, limited by our TimeTicks implementation, but as close as
   // possible.
   UMA_HISTOGRAM_CUSTOM_COUNTS("Extensions.ApiBindingObjectGenerationTime",
                               timer.Elapsed().InMicroseconds(),
                               1, 10000000, 100);
   // return result;
   return scope.Escape(object);
 }
 
 }  // namespace extensions