Why is memory leaking in Android in a newly created application template?

Question

Android

A question based on a topic on Habré What are memory leaks in android, how to check p... .
Using MAT, in my application I found a memory leak in mContext, but I did not find where exactly. For the experiment, I created a new project in Eclipse, without changing anything in it, launched it as is, and MAT also finds the same memory leak in it! How so?
Freshly created application code:

package com.example.test_mat;

import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;

public class MainActivity extends ActionBarActivity {

  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
  }

  @Override
  public boolean onCreateOptionsMenu(Menu menu) {
    // Inflate the menu; this adds items to the action bar if it is present.
    getMenuInflater().inflate(R.menu.main, menu);
    return true;
  }

  @Override
  public boolean onOptionsItemSelected(MenuItem item) {
    // Handle action bar item clicks here. The action bar will
    // automatically handle clicks on the Home/Up button, so long
    // as you specify a parent activity in AndroidManifest.xml.
    int id = item.getItemId();
    if (id == R.id.action_settings) {
      return true;
    }
    return super.onOptionsItemSelected(item);
  }
}

And here is what MAT shows:

Answer 1

Try just
public class MainActivity extends Activity
See if the memory leak persists?

Answer 2

Choate your tasks (as well as their solutions) one more beautiful than the other.
ideone.com/VkmZZx

Answer 3

If it is fundamental to use recursion, and if you need one line, then you do not need to do "echo" inside the function, but fasten the lines. More or less like this:

function number_string ($n = 5)
{
    return $n>1 ? number_string($n-1) . $n : $n;
}
echo number_string();