Lazy creating of background pages --enable-lazy-background-pages)

chrome/browser/extensions/extension_process_manager.cc

Index: chrome/browser/extensions/extension_process_manager.cc
diff --git a/chrome/browser/extensions/extension_process_manager.cc b/chrome/browser/extensions/extension_process_manager.cc
index f64624c2588ff844e10f21e1eb4623c78bb0b87d..8090581a3b3a2cd909bd7f8f1a0904f2cc16a30d 100644
--- a/chrome/browser/extensions/extension_process_manager.cc
+++ b/chrome/browser/extensions/extension_process_manager.cc
@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+#include "base/command_line.h"
 #include "chrome/browser/extensions/extension_process_manager.h"
 
 #include "chrome/browser/ui/browser_window.h"
@@ -14,6 +15,7 @@
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/ui/browser.h"
 #include "chrome/common/chrome_notification_types.h"
+#include "chrome/common/chrome_switches.h"
 #include "chrome/common/extensions/extension.h"
 #include "chrome/common/url_constants.h"
 #include "content/browser/site_instance.h"
@@ -55,10 +57,12 @@ class IncognitoExtensionProcessManager : public ExtensionProcessManager {
   ExtensionProcessManager* original_manager_;
 };
 
-static void CreateBackgroundHost(
+static void MaybeCreateBackgroundHost(

[Aaron Boodman, 2011/08/18 19:25:55]

Sorry to nitpick the but "Maybe" functions always bug me. Maybe based on what?
The name doesn't describe what the function does very well.

How about names like:

CreateBackgroundHosts -> CreateBackgroundHostsForProfileStartup
CreateBackgroundHost -> CreateBackgroundHostForExtensionLoad

I realize they are a bit long, but at least they try to describe the behavior.
And then you could just have a separate CreateBackgroundHost that does it
unconditionally.

[Tessa MacDuff, 2011/08/23 18:18:42]

Done.  I also moved the switch check up out of these functions to Observe(). 
Let me know what you think.

     ExtensionProcessManager* manager, const Extension* extension) {
-  // Start the process for the master page, if it exists.
-  if (extension->background_url().is_valid())
+  // Start the process for the master page, if it exists and we're not lazy.
+  if (extension->background_url().is_valid() &&
+      !CommandLine::ForCurrentProcess()->HasSwitch(
+          switches::kEnableLazyBackgroundPages))
     manager->CreateBackgroundHost(extension, extension->background_url());
 }
 
@@ -66,7 +70,7 @@ static void CreateBackgroundHosts(
     ExtensionProcessManager* manager, const ExtensionList* extensions) {
   for (ExtensionList::const_iterator extension = extensions->begin();
        extension != extensions->end(); ++extension) {
-    CreateBackgroundHost(manager, *extension);
+    MaybeCreateBackgroundHost(manager, *extension);
   }
 }
 
@@ -298,7 +302,7 @@ void ExtensionProcessManager::Observe(int type,
           Source<Profile>(source).ptr()->GetExtensionService();
       if (service->is_ready()) {
         const Extension* extension = Details<const Extension>(details).ptr();
-        ::CreateBackgroundHost(this, extension);
+        ::MaybeCreateBackgroundHost(this, extension);
       }
       break;
     }