[DevTools] Split DevToolsHttpHandler into two classes

extensions/shell/browser/shell_browser_main_parts.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/shell/browser/shell_browser_main_parts.h"
 
 #include "base/command_line.h"
 #include "base/run_loop.h"
 #include "components/keyed_service/content/browser_context_dependency_manager.h"
 #include "components/omaha_query_params/omaha_query_params.h"
@@ skipping 62 matching lines @@
     const content::MainFunctionParams& parameters,
     ShellBrowserMainDelegate* browser_main_delegate)
     : devtools_http_handler_(nullptr),
       extension_system_(nullptr),
       parameters_(parameters),
       run_message_loop_(true),
       browser_main_delegate_(browser_main_delegate) {
 }
 
 ShellBrowserMainParts::~ShellBrowserMainParts() {
-  if (devtools_http_handler_) {
-    // Note that Stop destroys devtools_http_handler_.
-    devtools_http_handler_->Stop();
-  }
+  DCHECK(!devtools_http_handler_);
 }
 
 void ShellBrowserMainParts::PreMainMessageLoopStart() {
   // TODO(jamescook): Initialize touch here?
 }
 
 void ShellBrowserMainParts::PostMainMessageLoopStart() {
 #if defined(OS_CHROMEOS)
   // Perform initialization of D-Bus objects here rather than in the below
   // helper classes so those classes' tests can initialize stub versions of the
@@ skipping 118 matching lines @@
     return true;
   // TODO(yoz): just return false here?
   base::RunLoop run_loop;
   run_loop.Run();
   *result_code = content::RESULT_CODE_NORMAL_EXIT;
   return true;
 }
 
 void ShellBrowserMainParts::PostMainMessageLoopRun() {
   browser_main_delegate_->Shutdown();
+  if (devtools_http_handler_) {
+    // Note that Stop destroys devtools_http_handler_.
+    devtools_http_handler_->Stop();
+    devtools_http_handler_ = nullptr;
+  }
 
 #if !defined(DISABLE_NACL)
   task_tracker_.TryCancelAll();
   nacl::NaClBrowser::SetDelegate(nullptr);
 #endif
 
   oauth2_token_service_.reset();
   BrowserContextDependencyManager::GetInstance()->DestroyBrowserContextServices(
       browser_context_.get());
   extension_system_ = NULL;
@@ skipping 17 matching lines @@
 }
 
 void ShellBrowserMainParts::CreateExtensionSystem() {
   DCHECK(browser_context_);
   extension_system_ = static_cast<ShellExtensionSystem*>(
       ExtensionSystem::Get(browser_context_.get()));
   extension_system_->InitForRegularProfile(true);
 }
 
 }  // namespace extensions