Support sharing of ContentMain and BrowserMain code with embedded use cases (try #3).

content/public/app/content_main_delegate.h

Index: content/public/app/content_main_delegate.h
===================================================================
--- content/public/app/content_main_delegate.h	(revision 121246)
+++ content/public/app/content_main_delegate.h	(working copy)
@@ -1,4 +1,4 @@
-// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Copyright (c) 2012 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.
 
@@ -34,7 +34,7 @@
   // has been initialized.
   virtual void SandboxInitialized(const std::string& process_type) = 0;
 
-  // Asks the embedder to start a process that content doesn't know about.
+  // Asks the embedder to start a process. Return -1 for the default behavior.
   virtual int RunProcess(
       const std::string& process_type,
       const content::MainFunctionParams& main_function_params) = 0;