title: Issue connecting GoogleApiClient in multiple activities
body: <p>I was, for the first time, trying to implement a google play services leader board but have some issue.</p>
  
  <p>I have the show leaderboard button in the main activity, so I initialize an GoogleApiClient in MainActivity, all good so far - google connects, and a blank leaderboard.</p>
  
  <p>The score that actually fills the leaderboard is obtained from second activity, the GameActivity.
  I create yet another instance of GoogleApiClient and try connecting it.
  But.. it always fails, even after calling apiClient.connect()</p>
  
  <p>Am I doing something wrong? Is only 1 client allowed throughout the program?</p>
  
  <p>I use this code in both of the activities to initialize:</p>
  
  <pre><code>apiClient = new GoogleApiClient.Builder(this)
              .addApi(Games.API)
              .addScope(Games.SCOPE_GAMES)
              .enableAutoManage(this, new GoogleApiClient.OnConnectionFailedListener() {
                  @Override
                  public void onConnectionFailed(@NonNull ConnectionResult connectionResult) {
                      Toast.makeText(LevelSelector.this, "Failed to connect to google play", Toast.LENGTH_LONG).show();
                  }
              })
              .build();
  </code></pre>
  
  <p>I call leaderboard from the main activity</p>
  
  <pre><code>    leaderboardTextView = (TextView) findViewById(R.id.leaderboard_button);
      leaderboardTextView.setOnClickListener(new View.OnClickListener() {
          @Override
          public void onClick(View view) {
              startActivityForResult(
                      Games.Leaderboards.getLeaderboardIntent(apiClient,
                              getString(R.string.leaderboard_most_stars)), 0);
          }
      });
  </code></pre>
  
  <p>And the score is submitted to leaderboard from a different activity</p>
  
  <pre><code>private void updateScore(){
      if(!apiClient.isConnected()){
          apiClient.connect();
      }
      //Always returns false.
      if(apiClient.isConnected()) {
          Games.Leaderboards.submitScore(apiClient,
                  getString(R.string.leaderboard_most_stars),
                  totalStars);
      }
  }
  </code></pre>