Simplify the ApplicationLoader interface in preparation for changes.

shell/android/native_viewport_application_loader.cc

Index: shell/android/native_viewport_application_loader.cc
diff --git a/shell/android/native_viewport_application_loader.cc b/shell/android/native_viewport_application_loader.cc
index cd27ba472375c835efef6ef5a182e18aad77d267..3e8c76e80e27d67d48f9ecb2d1787d4f1fe9662b 100644
--- a/shell/android/native_viewport_application_loader.cc
+++ b/shell/android/native_viewport_application_loader.cc
@@ -18,10 +18,8 @@ NativeViewportApplicationLoader::~NativeViewportApplicationLoader() {
 }
 
 void NativeViewportApplicationLoader::Load(
-    ApplicationManager* manager,
     const GURL& url,
-    InterfaceRequest<Application> application_request,
-    LoadCallback callback) {
+    InterfaceRequest<Application> application_request) {
   DCHECK(application_request.is_pending());
   app_.reset(new ApplicationImpl(this, application_request.Pass()));
 }