Fix one minor lint issue with wearable samples.

Fragment default constructor needed for resume, and fragment
can access main activity directly with a cast.

Change-Id: Id34f8abd664d17bc6cb9d31dbfcb197be0bfdc64
diff --git a/wearable/wear/JumpingJack/Wearable/src/main/java/com/example/android/wearable/jumpingjack/MainActivity.java b/wearable/wear/JumpingJack/Wearable/src/main/java/com/example/android/wearable/jumpingjack/MainActivity.java
index cdaaf6e..f1589c7 100644
--- a/wearable/wear/JumpingJack/Wearable/src/main/java/com/example/android/wearable/jumpingjack/MainActivity.java
+++ b/wearable/wear/JumpingJack/Wearable/src/main/java/com/example/android/wearable/jumpingjack/MainActivity.java
@@ -99,7 +99,7 @@
         mSecondIndicator = (ImageView) findViewById(R.id.indicator_1);
         final PagerAdapter adapter = new PagerAdapter(getFragmentManager());
         mCounterPage = new CounterFragment();
-        mSettingPage = new SettingsFragment(this);
+        mSettingPage = new SettingsFragment();
         adapter.addFragment(mCounterPage);
         adapter.addFragment(mSettingPage);
         setIndicator(0);
diff --git a/wearable/wear/JumpingJack/Wearable/src/main/java/com/example/android/wearable/jumpingjack/fragments/SettingsFragment.java b/wearable/wear/JumpingJack/Wearable/src/main/java/com/example/android/wearable/jumpingjack/fragments/SettingsFragment.java
index fffe8fb..771abd3 100644
--- a/wearable/wear/JumpingJack/Wearable/src/main/java/com/example/android/wearable/jumpingjack/fragments/SettingsFragment.java
+++ b/wearable/wear/JumpingJack/Wearable/src/main/java/com/example/android/wearable/jumpingjack/fragments/SettingsFragment.java
@@ -31,22 +31,15 @@
  */
 public class SettingsFragment extends Fragment {
 
-    private Button mButton;
-    private MainActivity mMainActivity;
-
-    public SettingsFragment(MainActivity mainActivity) {
-        mMainActivity = mainActivity;
-    }
-
     @Override
     public View onCreateView(LayoutInflater inflater, ViewGroup container,
             Bundle savedInstanceState) {
         View view = inflater.inflate(R.layout.setting_layout, container, false);
-        mButton = (Button) view.findViewById(R.id.btn);
-        mButton.setOnClickListener(new View.OnClickListener() {
+        Button button = (Button) view.findViewById(R.id.btn);
+        button.setOnClickListener(new View.OnClickListener() {
             @Override
             public void onClick(View v) {
-                mMainActivity.resetCounter();
+                ((MainActivity) getActivity()).resetCounter();
             }
         });
         return view;