title: onAutoFocus not called in android camera
body: <p>I have set the focus mode as FOCUS_MODE_AUTO.</p>
  
  <pre><code>camParameters.setFocusMode(Camera.Parameters.FOCUS_MODE_AUTO);
  cameraInstance.setParameters(camParameters);
  </code></pre>
  
  <p>Then I have started the preview.</p>
  
  <pre><code>cameraInstance.startPreview();
  </code></pre>
  
  <p>After that I am calling the autofocus method.</p>
  
  <pre><code>List&lt;String&gt; focusModes = camParameters.getSupportedFocusModes();
                  if(focusModes != null &amp;&amp; focusModes.contains(Camera.Parameters.FOCUS_MODE_AUTO)) {
                      Log.d(TAG, "Phone supports autofocus!");
                      cameraInstance.autoFocus(autoFocusCallback);
                  }
  </code></pre>
  
  <p>Here is my autofocus callback.</p>
  
  <pre><code>private static android.hardware.Camera.AutoFocusCallback autoFocusCallback = new android.hardware.Camera.AutoFocusCallback() {
  
      @Override
      public void onAutoFocus (boolean success,
                               Camera camera) {
          if(success) {
              Log.d(TAG, "Sharp");
              camera.cancelAutoFocus();
          } else {
              Log.d(TAG, "Not Sharp");
              camera.autoFocus(autoFocusCallback);
          }
      }
  };
  </code></pre>
  
  <p>I found that the onAutoFocus method is not called after I see the camera preview and noted(in logcat) that the following error is continuously spawning.</p>
  
  <p>01-01 08:29:07.135 765-10897/? <strong>E/mm-camera:  5052: af_port_handle_set_focus_manual_pos_evt: not in CAM_FOCUS_MODE_OFF(Manual) mode,           ignore the settings</strong></p>
  
  <p>01-01 08:29:07.316 765-10891/? <strong>E/mm-camera:  739: af_process_update_fv_history: SW Stats missing!Start Waiting</strong></p>