Settings: Remove all unused imports.

Change-Id: Iebfa52cb849d69974c94902b0b020893cf5618a3

src/com/android/settings/wifi/WifiAPITest.java

@@ -20,7 +20,6 @@ import com.android.settings.R;
 
 import android.app.AlertDialog;
 import android.content.DialogInterface;
-import android.content.Intent;
 import android.net.wifi.WifiManager;
 
 import android.os.Bundle;

src/com/android/settings/wifi/WifiScanModeActivity.java

@@ -29,7 +29,6 @@ import android.content.pm.PackageManager;
 import android.net.wifi.WifiManager;
 import android.os.Bundle;
 import android.provider.Settings;
-import android.util.Log;
 
 /**
  * This activity requests users permission to allow scanning even when Wi-Fi is turned off

src/com/android/settings/wifi/WriteWifiConfigToNfcDialog.java

@@ -34,13 +34,11 @@ import android.text.Editable;
 import android.text.InputType;
 import android.text.TextWatcher;
 import android.util.Log;
-import android.view.Gravity;
 import android.view.View;
 import android.view.inputmethod.InputMethodManager;
 import android.widget.Button;
 import android.widget.CheckBox;
 import android.widget.CompoundButton;
-import android.widget.LinearLayout;
 import android.widget.ProgressBar;
 import android.widget.TextView;