Switch platform apps from a declarative launch container to handling an onLaunched event.

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

Index: chrome/browser/extensions/api/runtime/runtime_api.cc
diff --git a/chrome/browser/extensions/api/runtime/runtime_api.cc b/chrome/browser/extensions/api/runtime/runtime_api.cc
index c2e541bf378f0dc3f815fed43dfc016b7cbd8c82..330069ba4e9823ab9a96d07da0e04a6da0f10172 100644
--- a/chrome/browser/extensions/api/runtime/runtime_api.cc
+++ b/chrome/browser/extensions/api/runtime/runtime_api.cc
@@ -12,6 +12,7 @@
 namespace {
 
 const char kOnInstalledEvent[] = "experimental.runtime.onInstalled";
+const char kOnLaunchedEvent[] = "experimental.runtime.onLaunched";
 
 }
 
@@ -31,4 +32,10 @@ void RuntimeEventRouter::DispatchOnInstalledEvent(
       extension->id(), kOnInstalledEvent, "[]", NULL, GURL());
 }
 
+void RuntimeEventRouter::DispatchOnLaunchedEvent(
+    Profile* profile, const Extension* extension) {
+  profile->GetExtensionEventRouter()->DispatchEventToExtension(
+      extension->id(), kOnLaunchedEvent, "[]", NULL, GURL());
+}
+
 }   // namespace extensions