Defer shutting down Chrome after the CF automation connection goes away.

chrome/browser/automation/chrome_frame_automation_provider.cc

Index: chrome/browser/automation/chrome_frame_automation_provider.cc
diff --git a/chrome/browser/automation/chrome_frame_automation_provider.cc b/chrome/browser/automation/chrome_frame_automation_provider.cc
index ce2f6a42d095bb7cad8534ab2d900338073a8ffc..232be3c8348aaadb9e33e4158e75c3f200dd34a0 100644
--- a/chrome/browser/automation/chrome_frame_automation_provider.cc
+++ b/chrome/browser/automation/chrome_frame_automation_provider.cc
@@ -1,15 +1,23 @@
-// 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.
 
 #include "chrome/browser/automation/chrome_frame_automation_provider.h"
+
+#include <algorithm>
+
+#include "base/command_line.h"
+#include "base/string_number_conversions.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/profiles/profile_manager.h"
 #include "chrome/common/automation_messages.h"
+#include "chrome/common/chrome_switches.h"
 #include "ipc/ipc_message.h"
 #include "ipc/ipc_channel.h"
 
+const int kMaxChromeShutdownDelaySeconds = 60*60;
+
 ChromeFrameAutomationProvider::ChromeFrameAutomationProvider(Profile* profile)
     : AutomationProvider(profile) {
   DCHECK(g_browser_process);
@@ -19,8 +27,38 @@ ChromeFrameAutomationProvider::ChromeFrameAutomationProvider(Profile* profile)
 
 ChromeFrameAutomationProvider::~ChromeFrameAutomationProvider() {
   DCHECK(g_browser_process);
-  if (g_browser_process)
-    g_browser_process->ReleaseModule();
+  if (g_browser_process) {
+    CommandLine& cmd_line = *CommandLine::ForCurrentProcess();
+
+    CommandLine::StringType shutdown_delay(
+        cmd_line.GetSwitchValueNative(switches::kChromeFrameShutdownDelay));
+    if (!shutdown_delay.empty()) {
+      VLOG(1) << "ChromeFrameAutomationProvider: "
+                 "Scheduling ReleaseBrowserProcess.";
+
+      // Grab the specified shutdown delay.
+      int shutdown_delay_seconds = 0;
+      base::StringToInt(shutdown_delay, &shutdown_delay_seconds);
+
+      // Clamp to reasonable values.
+      shutdown_delay_seconds = std::max(0, shutdown_delay_seconds);
+      shutdown_delay_seconds = std::min(shutdown_delay_seconds,
+                                        kMaxChromeShutdownDelaySeconds);
+
+      // We have Chrome Frame defer Chrome shutdown for a time to improve
+      // intra-page load times.
+      // Note that we are tracking the perf impact of this under
+      // http://crbug.com/98506
+      MessageLoop::current()->PostDelayedTask(
+          FROM_HERE,
+          base::Bind(&ChromeFrameAutomationProvider::ReleaseBrowserProcess),
+          base::TimeDelta::FromSeconds(shutdown_delay_seconds));
+    } else {
+      VLOG(1) << "ChromeFrameAutomationProvider: "
+                 "Releasing browser module with no delay.";
+      g_browser_process->ReleaseModule();
+    }
+  }
 }
 
 bool ChromeFrameAutomationProvider::OnMessageReceived(
@@ -86,3 +124,12 @@ bool ChromeFrameAutomationProvider::IsValidMessage(uint32 type) {
 
   return is_valid_message;
 }
+
+// static
+void ChromeFrameAutomationProvider::ReleaseBrowserProcess() {
+  if (g_browser_process) {
+    VLOG(1) << "ChromeFrameAutomationProvider: "
+               "Releasing browser process.";
+    g_browser_process->ReleaseModule();
+  }
+}