Extract chrome.runtime API code from extensions::EventRouter

chrome/browser/extensions/api/runtime/runtime_api.h

Index: chrome/browser/extensions/api/runtime/runtime_api.h
diff --git a/chrome/browser/extensions/api/runtime/runtime_api.h b/chrome/browser/extensions/api/runtime/runtime_api.h
index 14c5f79e956ff88dcf455423dc06c3ea5ed54158..abd966757c54a1f499157a6228ad35699216dadc 100644
--- a/chrome/browser/extensions/api/runtime/runtime_api.h
+++ b/chrome/browser/extensions/api/runtime/runtime_api.h
@@ -9,6 +9,7 @@
 
 #include "chrome/browser/extensions/chrome_extension_function.h"
 #include "chrome/common/extensions/api/runtime.h"
+#include "components/browser_context_keyed_service/browser_context_keyed_service.h"
 #include "content/public/browser/notification_observer.h"
 #include "content/public/browser/notification_registrar.h"
 
@@ -26,6 +27,36 @@ namespace extensions {
 class Extension;
 class ExtensionHost;
 
+// Runtime API dispatches onStartup, onInstalled, and similar events to
+// extensions. There is one instance shared between a browser context and
+// its related incognito instance.
+class RuntimeAPI : public BrowserContextKeyedService,

[James Cook, 2013/11/14 01:34:02]

I decided to make this a BCKS instead of a ProfileKeyedAPI because it doesn't
actually need Profile (BrowserContext is enough) and I think this will make it
easier to move into src/extensions later.

+                   public content::NotificationObserver {
+ public:
+  explicit RuntimeAPI(content::BrowserContext* context);
+  virtual ~RuntimeAPI();
+
+  // content::NotificationObserver overrides:
+  virtual void Observe(int type,
+                       const content::NotificationSource& source,
+                       const content::NotificationDetails& details) OVERRIDE;
+
+ private:
+  void OnExtensionsReady();
+  void OnExtensionLoaded(const Extension* extension);
+  void OnExtensionInstalled(const Extension* extension);
+
+  content::BrowserContext* browser_context_;
+
+  // True if we should dispatch the chrome.runtime.onInstalled event with
+  // reason "chrome_update" upon loading each extension.
+  bool dispatch_chrome_updated_event_;
+
+  content::NotificationRegistrar registrar_;
+
+  DISALLOW_COPY_AND_ASSIGN(RuntimeAPI);
+};
+
 class RuntimeEventRouter {
  public:
   // Dispatches the onStartup event to all currently-loaded extensions.