Send an onInstalled event for shared module update

apps/shell/browser/shell_extension_system.cc

Index: apps/shell/browser/shell_extension_system.cc
diff --git a/apps/shell/browser/shell_extension_system.cc b/apps/shell/browser/shell_extension_system.cc
index 7d56884fcf6bc3e02b7a49a93d104952acbc857e..2aefddfbbf3f4c91e1a7f531ea0f490528da0ca8 100644
--- a/apps/shell/browser/shell_extension_system.cc
+++ b/apps/shell/browser/shell_extension_system.cc
@@ -180,4 +180,10 @@ ContentVerifier* ShellExtensionSystem::content_verifier() {
   return NULL;
 }
 
+scoped_ptr<const ExtensionSet> ShellExtensionSystem::GetDependentExtensions(
+    const Extension* extension) {
+  scoped_ptr<ExtensionSet> empty(new ExtensionSet());
+  return empty.PassAs<const ExtensionSet>();
+}
+
 }  // namespace extensions