arc: Support running Arc app in shelf

components/arc/test/fake_app_instance.cc

Index: components/arc/test/fake_app_instance.cc
diff --git a/components/arc/test/fake_app_instance.cc b/components/arc/test/fake_app_instance.cc
index 46b069cf2a11442617950eed50baa513cc859b66..285040bff04a4c87899edb8a89c6b3dc332cd2eb 100644
--- a/components/arc/test/fake_app_instance.cc
+++ b/components/arc/test/fake_app_instance.cc
@@ -107,6 +107,12 @@ bool FakeAppInstance::GenerateAndSendIcon(const AppInfo& app,
   return true;
 }
 
+void FakeAppInstance::SetTaskInfo(int task_id,
+                                  const std::string& package_name,
+                                  const std::string& activity) {
+  task_id_to_info_[task_id].reset(new Request(package_name, activity));
+}
+
 void FakeAppInstance::WaitForIncomingMethodCall() {
   binding_.WaitForIncomingMethodCall();
 }
@@ -136,4 +142,13 @@ void FakeAppInstance::CanHandleResolution(const mojo::String& package_name,
 void FakeAppInstance::UninstallPackage(const mojo::String& package_name) {
 }
 
+void FakeAppInstance::GetTaskInfo(int32_t task_id,
+                                  const GetTaskInfoCallback& callback) {
+  TaskIdToInfo::const_iterator it = task_id_to_info_.find(task_id);
+  if (it != task_id_to_info_.end()) {
+    callback.Run(it->second->package_name(), it->second->activity());
+    return;
+  }

[Mr4D (OOO till 08-26), 2016/03/24 23:03:46]

Just checking - does a "non callback" in case of an error stall the test?

[khmel, 2016/03/24 23:56:53]

I like your question :) Actually it does not stall but mojo is not happy and
crashes with assert that callback is not called. So, we have to call. In case of
not-found, I call empty package name and activity.

+}
+
 }  // namespace arc