Add --auto-open-devtools-for-tabs flag.

chrome/browser/chrome_browser_main.cc

 // 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.
 
 #include "chrome/browser/chrome_browser_main.h"
 
 #include <stddef.h>
 #include <stdint.h>
 #include <set>
 #include <string>
@@ skipping 1168 matching lines @@
 void ChromeBrowserMainParts::PostProfileInit() {
   TRACE_EVENT0("startup", "ChromeBrowserMainParts::PostProfileInit");
 
 #if BUILDFLAG(ANDROID_JAVA_UI)
   DevToolsDiscoveryProviderAndroid::Install();
 #else
   ChromeDevToolsDiscoveryProvider::Install();
 #endif  // BUILDFLAG(ANDROID_JAVA_UI)
 
   LaunchDevToolsHandlerIfNeeded(parsed_command_line());
+  if (parsed_command_line().HasSwitch(::switches::kAutoOpenDevToolsForTabs))
+    g_browser_process->CreateDevToolsAutoOpener();
+
   for (size_t i = 0; i < chrome_extra_parts_.size(); ++i)
     chrome_extra_parts_[i]->PostProfileInit();
 }
 
 void ChromeBrowserMainParts::PreBrowserStart() {
   TRACE_EVENT0("startup", "ChromeBrowserMainParts::PreBrowserStart");
   for (size_t i = 0; i < chrome_extra_parts_.size(); ++i)
     chrome_extra_parts_[i]->PreBrowserStart();
 
   three_d_observer_.reset(new ThreeDAPIObserver());
@@ skipping 692 matching lines @@
   chromeos::CrosSettings::Shutdown();
 #endif  // defined(OS_CHROMEOS)
 #endif  // defined(OS_ANDROID)
 }
 
 // Public members:
 
 void ChromeBrowserMainParts::AddParts(ChromeBrowserMainExtraParts* parts) {
   chrome_extra_parts_.push_back(parts);
 }