Simplify the ApplicationLoader interface in preparation for changes.

shell/android/android_handler_loader.cc

Index: shell/android/android_handler_loader.cc
diff --git a/shell/android/android_handler_loader.cc b/shell/android/android_handler_loader.cc
index 1b334f317e2a5f917d242676b98c4f4383bceb72..abbf8d70746a597ec24a8c1d0f66e6b14e0dcc69 100644
--- a/shell/android/android_handler_loader.cc
+++ b/shell/android/android_handler_loader.cc
@@ -14,10 +14,8 @@ AndroidHandlerLoader::~AndroidHandlerLoader() {
 }
 
 void AndroidHandlerLoader::Load(
-    ApplicationManager* manager,
     const GURL& url,
-    InterfaceRequest<Application> application_request,
-    LoadCallback callback) {
+    InterfaceRequest<Application> application_request) {
   DCHECK(application_request.is_pending());
   application_.reset(
       new ApplicationImpl(&android_handler_, application_request.Pass()));