Fork renderer process for webview

Previously it was disabled because Chrome doesn't support swapping
renderer process before, it seeems to work fine now, so we enable it to
see how it goes.

atom/renderer/atom_renderer_client.cc

@@ -52,10 +52,6 @@ bool IsSwitchEnabled(base::CommandLine* command_line,
   return true;
 }
 
-bool IsGuestFrame(blink::WebFrame* frame) {
-  return frame->uniqueName().utf8() == "ATOM_SHELL_GUEST_WEB_VIEW";
-}
-
 // global.Uint8Array;
 v8::Local<v8::Function> GetUint8ArrayConstructor(
     v8::Isolate* isolate, v8::Local<v8::Context> context) {
@@ -189,14 +185,11 @@ bool AtomRendererClient::OverrideCreatePlugin(
 void AtomRendererClient::DidCreateScriptContext(
     blink::WebFrame* frame,
     v8::Handle<v8::Context> context) {
-  // Only attach node bindings in main frame or guest frame.
-  if (!IsGuestFrame(frame)) {
   if (main_frame_)
     return;
 
   // The first web frame is the main frame.
   main_frame_ = frame;
-  }
 
   // Give the node loop a run to make sure everything is ready.
   node_bindings_->RunMessageLoop();
@@ -221,10 +214,6 @@ bool AtomRendererClient::ShouldFork(blink::WebFrame* frame,
                                     bool is_initial_navigation,
                                     bool is_server_redirect,
                                     bool* send_referrer) {
-  // Never fork renderer process for guests.
-  if (IsGuestFrame(frame))
-    return false;
-
   // Handle all the navigations and reloads in browser.
   // FIXME We only support GET here because http method will be ignored when
   // the OpenURLFromTab is triggered, which means form posting would not work,

atom/renderer/lib/init.coffee

@@ -29,8 +29,6 @@ for arg in process.argv
   if arg.indexOf('--guest-instance-id=') == 0
     # This is a guest web view.
     process.guestInstanceId = parseInt arg.substr(arg.indexOf('=') + 1)
-    # Set the frame name to make AtomRendererClient recognize this guest.
-    require('web-frame').setName 'ATOM_SHELL_GUEST_WEB_VIEW'
   else if arg.indexOf('--node-integration=') == 0
     nodeIntegration = arg.substr arg.indexOf('=') + 1
   else if arg.indexOf('--preload=') == 0