make "reload" on chrome://extensions automatically relaunch running apps

chrome/browser/ui/webui/extensions/extension_settings_handler.cc

Index: chrome/browser/ui/webui/extensions/extension_settings_handler.cc
diff --git a/chrome/browser/ui/webui/extensions/extension_settings_handler.cc b/chrome/browser/ui/webui/extensions/extension_settings_handler.cc
index 1605be8e34c3544b53109b4e68bceeae01e27ec9..d3a17b2c9f345488653920efe4621d35ea962dc0 100644
--- a/chrome/browser/ui/webui/extensions/extension_settings_handler.cc
+++ b/chrome/browser/ui/webui/extensions/extension_settings_handler.cc
@@ -29,6 +29,7 @@
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/tab_contents/background_contents.h"
 #include "chrome/browser/ui/browser_finder.h"
+#include "chrome/browser/ui/extensions/application_launch.h"
 #include "chrome/browser/ui/webui/extensions/extension_icon_source.h"
 #include "chrome/browser/view_type_utils.h"
 #include "chrome/common/chrome_notification_types.h"
@@ -71,7 +72,8 @@ ExtensionSettingsHandler::ExtensionSettingsHandler()
       management_policy_(NULL),
       ignore_notifications_(false),
       deleting_rvh_(NULL),
-      registered_for_notifications_(false) {
+      registered_for_notifications_(false),
+      ALLOW_THIS_IN_INITIALIZER_LIST(weak_factory_(this)) {
 }
 
 ExtensionSettingsHandler::~ExtensionSettingsHandler() {
@@ -89,7 +91,8 @@ ExtensionSettingsHandler::ExtensionSettingsHandler(ExtensionService* service,
       management_policy_(policy),
       ignore_notifications_(false),
       deleting_rvh_(NULL),
-      registered_for_notifications_(false) {
+      registered_for_notifications_(false),
+      ALLOW_THIS_IN_INITIALIZER_LIST(weak_factory_(this)) {
 }
 
 // static
@@ -396,10 +399,34 @@ void ExtensionSettingsHandler::Observe(
     case chrome::NOTIFICATION_EXTENSION_HOST_CREATED:
       source_profile = content::Source<Profile>(source).ptr();
       if (!profile->IsSameProfile(source_profile))
-          return;
+        return;
+      MaybeUpdateAfterNotification();
+      break;
+    case chrome::NOTIFICATION_EXTENSION_LOADED: {
+      source_profile = content::Source<Profile>(source).ptr();
+      const Extension* extension =
+          content::Details<const Extension>(details).ptr();
+      std::list<std::string>::iterator iter =
+          std::find(relaunch_app_ids_.begin(), relaunch_app_ids_.end(),
+                    extension->id());
+
+      if (profile->IsSameProfile(source_profile) &&
+          iter != relaunch_app_ids_.end()) {
+        relaunch_app_ids_.erase(iter);
+        // For platform apps, there's not a really good way to know when the
+        // background page has started up and is ready to receive the
+        // onLaunched event, so we just wait half a second.

[Evan Stade, 2012/06/22 05:17:51]

suggestions for improvement welcome.

[Aaron Boodman, 2012/06/22 05:35:02]

LazyBackgroundTaskQueue ?

[Evan Stade, 2012/06/22 19:39:51]

awesome

+        MessageLoop::current()->PostDelayedTask(
+            FROM_HERE,
+            base::Bind(&ExtensionSettingsHandler::LaunchApplication,
+                       weak_factory_.GetWeakPtr(),
+                       extension->id()),
+            base::TimeDelta::FromMilliseconds(500));
+      }
+
       MaybeUpdateAfterNotification();
       break;
-    case chrome::NOTIFICATION_EXTENSION_LOADED:
+    }
     case chrome::NOTIFICATION_EXTENSION_UNLOADED:
     case chrome::NOTIFICATION_EXTENSION_UPDATE_DISABLED:
     case chrome::NOTIFICATION_EXTENSION_WARNING_CHANGED:
@@ -412,6 +439,22 @@ void ExtensionSettingsHandler::Observe(
   }
 }
 
+void ExtensionSettingsHandler::LaunchApplication(
+    const std::string& extension_id) {
+  const Extension* extension =
+      extension_service_->GetExtensionById(extension_id, false);
+  if (!extension)
+    return;
+
+  extension_misc::LaunchContainer launch_container =
+      extension_service_->extension_prefs()->GetLaunchContainer(
+          extension, ExtensionPrefs::LAUNCH_REGULAR);
+
+  application_launch::OpenApplication(
+      extension_service_->profile(), extension, launch_container, GURL(),
+      NEW_BACKGROUND_TAB, NULL);
+}
+
 void ExtensionSettingsHandler::ExtensionUninstallAccepted() {
   DCHECK(!extension_id_prompting_.empty());
 
@@ -455,8 +498,21 @@ void ExtensionSettingsHandler::ReloadUnpackedExtensions() {
 
   for (std::vector<const Extension*>::iterator iter =
        unpacked_extensions.begin(); iter != unpacked_extensions.end(); ++iter) {
-    extension_service_->ReloadExtension((*iter)->id());
+    ReloadExtension(*iter);
+  }
+}
+
+void ExtensionSettingsHandler::ReloadExtension(
+    const Extension* extension) {
+  Profile* profile = Profile::FromWebUI(web_ui());
+  // If the extension is a platform app, and is "running" (i.e. has open render
+  // views), then mark it for relaunch later.

[Evan Stade, 2012/06/22 05:17:51]

this is kind of a hokey definition of "running", but it seems to do the trick
most of the time. You could imagine a platform app that does something which
doesn't create render views when you launch it, in which case this wouldn't be
able to determine that the app had been launched and needs relaunching.

[Aaron Boodman, 2012/06/22 05:35:02]

I think if there are no running render views, the app is by definition not
running.

You could also just check if there is any process for this extension. That would
be about the same.

[Evan Stade, 2012/06/22 19:39:51]

I don't want to count background pages.

[Aaron Boodman, 2012/06/22 20:30:54]

I'm surprised that the event page is not returned here. An EventPage is a
WebContents that contains a RVH. It seems like it should be returned, and is
probably a bug that will eventually be fixed if it isn't.

[Evan Stade, 2012/06/22 22:29:50]

oh, it does. I was confused because the background page was inactive at the
time.

+  if (extension->is_platform_app() &&
+      !profile->GetExtensionProcessManager()->
+          GetRenderViewHostsForExtension(extension->id()).empty()) {
+    relaunch_app_ids_.push_back(extension->id());
   }
+  extension_service_->ReloadExtension(extension->id());
 }
 
 void ExtensionSettingsHandler::HandleRequestExtensionsData(
@@ -581,7 +637,10 @@ void ExtensionSettingsHandler::HandleInspectMessage(const ListValue* args) {
 void ExtensionSettingsHandler::HandleReloadMessage(const ListValue* args) {
   std::string extension_id = UTF16ToUTF8(ExtractStringValue(args));
   CHECK(!extension_id.empty());
-  extension_service_->ReloadExtension(extension_id);
+
+  const Extension* extension =
+      extension_service_->GetExtensionById(extension_id, false);
+  ReloadExtension(extension);
 }
 
 void ExtensionSettingsHandler::HandleEnableMessage(const ListValue* args) {