Remove NOTIFICATION_EXTENSION_ENABLED.

chrome/browser/extensions/extension_service.cc

Index: chrome/browser/extensions/extension_service.cc
diff --git a/chrome/browser/extensions/extension_service.cc b/chrome/browser/extensions/extension_service.cc
index 865438513dd39f0ea0d461506492a3c0736b8112..a77c73d51519aadb93502e5570341ec2dfc05351 100644
--- a/chrome/browser/extensions/extension_service.cc
+++ b/chrome/browser/extensions/extension_service.cc
@@ -79,6 +79,7 @@
 #include "extensions/browser/extensions_browser_client.h"
 #include "extensions/browser/external_install_info.h"
 #include "extensions/browser/install_flag.h"
+#include "extensions/browser/lazy_background_task_queue.h"
 #include "extensions/browser/renderer_startup_helper.h"
 #include "extensions/browser/runtime_data.h"
 #include "extensions/browser/uninstall_reason.h"
@@ -144,6 +145,8 @@ const int kUpdateIdleDelay = 5;
 // TODO(samuong): Remove this in M58 (see comment in ExtensionService::Init).
 const char kDeprecatedLoadComponentExtension[] = "load-component-extension";
 
+void DoNothingWithExtensionHost(extensions::ExtensionHost* host) {}
+
 }  // namespace
 
 // ExtensionService.
@@ -924,11 +927,7 @@ void ExtensionService::EnableExtension(const std::string& extension_id) {
 
   NotifyExtensionLoaded(extension);
 
-  // Notify listeners that the extension was enabled.
-  content::NotificationService::current()->Notify(
-      extensions::NOTIFICATION_EXTENSION_ENABLED,
-      content::Source<Profile>(profile_),
-      content::Details<const Extension>(extension));
+  MaybeSpinUpLazyBackgroundPage(extension);
 }
 
 void ExtensionService::DisableExtension(const std::string& extension_id,
@@ -2557,3 +2556,29 @@ void ExtensionService::OnInstalledExtensionsLoaded() {
 
   OnBlacklistUpdated();
 }
+
+void ExtensionService::MaybeSpinUpLazyBackgroundPage(
+    const Extension* extension) {
+  if (!extensions::BackgroundInfo::HasLazyBackgroundPage(extension))
+    return;
+
+  // For orphaned devtools, we will reconnect devtools to it later in
+  // DidCreateRenderViewForBackgroundPage().
+  OrphanedDevTools::iterator iter = orphaned_dev_tools_.find(extension->id());
+  bool has_orphaned_dev_tools = iter != orphaned_dev_tools_.end();
+
+  // Reloading component extension does not trigger install, so RuntimeAPI won't
+  // be able to detect its loading. Therefore, we need to spin up its lazy
+  // background page.
+  bool is_component_extension =
+      Manifest::IsComponentLocation(extension->location());
+
+  if (!has_orphaned_dev_tools && !is_component_extension)
+    return;
+
+  // Wake up the event page by posting a dummy task.
+  extensions::LazyBackgroundTaskQueue* queue =
+      extensions::LazyBackgroundTaskQueue::Get(profile_);
+  queue->AddPendingTask(profile_, extension->id(),
+                        base::Bind(&DoNothingWithExtensionHost));
+}