Zygote most of the uses of the utility process on Linux

chrome/browser/extensions/extension_management_api.cc

 // Copyright (c) 2011 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 "chrome/browser/extensions/extension_management_api.h"
 
 #include <map>
 #include <string>
 
 #include "base/basictypes.h"
@@ skipping 194 matching lines @@
     CHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
     BrowserThread::PostTask(
         BrowserThread::IO,
         FROM_HERE,
         base::Bind(&SafeManifestJSONParser::StartWorkOnIOThread, this));
   }
 
   void StartWorkOnIOThread() {
     CHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
     utility_host_ = new UtilityProcessHost(this, BrowserThread::IO);
+#if defined(OS_LINUX)
+    utility_host_->set_should_use_zygote(true);

[Aaron Boodman, 2011/12/02 03:10:04]

Since most call sites want the zygote enabled, how about defaulting to true.

[Jorge Lucangeli Obes, 2011/12/02 18:27:16]

The good thing about defaulting to false is that we can't accidentally break
users of the utility process that are requiring FS access. I went through my
local checkout carefully and used code search to find all users of
UtilityProcessHost, but I felt it would be safer to keep the default as false.

[Jorge Lucangeli Obes, 2011/12/02 20:43:48]

Actually, scratch that. I'm pretty sure I got all the uses. Let's make the
default true.

+#endif
     utility_host_->Send(new ChromeUtilityMsg_ParseJSON(manifest_));
   }
 
   virtual bool OnMessageReceived(const IPC::Message& message) {
     bool handled = true;
     IPC_BEGIN_MESSAGE_MAP(SafeManifestJSONParser, message)
       IPC_MESSAGE_HANDLER(ChromeUtilityHostMsg_ParseJSON_Succeeded,
                           OnJSONParseSucceeded)
       IPC_MESSAGE_HANDLER(ChromeUtilityHostMsg_ParseJSON_Failed,
                           OnJSONParseFailed)
@@ skipping 283 matching lines @@
     bool escalated = prefs ->DidExtensionEscalatePermissions(extension->id());
     args.Append(CreateExtensionInfo(*extension, enabled, escalated));
   }
 
   std::string args_json;
   base::JSONWriter::Write(&args, false /* pretty_print */, &args_json);
 
   profile->GetExtensionEventRouter()->DispatchEventToRenderers(
       event_name, args_json, NULL, GURL());
 }