title: Android ActionBar.Tab setCustomView() doesn't fill_parent
body: <p>I'm using ActionBar.Tab setCustomView() method with this layout:</p>
  
  <pre><code>&lt;?xml version="1.0" encoding="utf-8"?&gt;
  &lt;RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
      android:layout_width="fill_parent"
      android:layout_height="fill_parent"
      android:background="@color/background_grey" &gt;
  
      &lt;TextView
          android:layout_width="fill_parent"
          android:layout_height="fill_parent"
          android:text="Test Tab" 
          android:textColor="@color/background_dark_green"/&gt;
  
  &lt;/RelativeLayout&gt;
  </code></pre>
  
  <p>this is my function setting the ActionBar:</p>
  
  <pre><code>public void setActionBar()
  {
      ActionBar actionBar = getSupportActionBar();
      //actionBar.hide();
      actionBar.setDisplayOptions(ActionBar.DISPLAY_SHOW_CUSTOM);
      actionBar.setDisplayShowHomeEnabled(false);
      actionBar.setDisplayShowTitleEnabled(false);        
      //set action bar navigation mode
      actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);        
      //set tabs      
      //home tab 
      Tab tab = actionBar.newTab().setText(TAB_HOME).setTabListener(new PicoTabListener&lt;StartFragment&gt;(this, StartFragment.class));       
      tab.setCustomView(R.layout.tab_background);
      actionBar.addTab(tab);
      //events tab
      tab = actionBar.newTab().setText(TAB_EVENTS).setTabListener(new PicoTabListener&lt;EventsFragment&gt;(this, EventsFragment.class));
      actionBar.addTab(tab);      
      //enter event code
      tab = actionBar.newTab().setText(TAB_CODE).setTabListener(new PicoTabListener&lt;EnterCodeFragment&gt;(this, EnterCodeFragment.class));
      actionBar.addTab(tab);      
  }
  </code></pre>
  
  <p>and my activity layout:</p>
  
  <pre><code>&lt;?xml version="1.0" encoding="utf-8"?&gt;
  &lt;!-- This is the main layout of the application --&gt;
  &lt;RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
      android:id="@+id/fragment_basic_root"
      android:layout_width="fill_parent"
      android:layout_height="fill_parent"
      android:background="@color/background_dark_green" &gt;
  
  &lt;/RelativeLayout&gt;
  </code></pre>
  
  <p>The results seams to look like this (The upper left tab with the gray background):
  <img src="https://i.stack.imgur.com/AUUxo.png" alt="enter image description here"></p>
  
  <p>How can i make my custom view to fill whole tab and work properly ?</p>
  
  <p>I'm using support package v7 for Android 2.3</p>