Revert "[Settings] Support getSystemService(Class<T>)"

Revert submission 1645152-getSystemService(Class<T>)

Reason for revert: Fix JUnit test failure
Reverted Changes:
I1b4812044:[Settings] Convert to getSystemService(Class<T>)
I278951c24:[Settings] Support getSystemService(Class<T>)

Change-Id: I5ca453c30c39d52e772033820f36ad448aeabe9e

src/com/android/settings/SettingsPreferenceFragment.java

@@ -438,13 +438,6 @@ public abstract class SettingsPreferenceFragment extends InstrumentedPreferenceF
         return getActivity().getSystemService(name);
     }
 
-    /**
-     * Returns the specified system service from the owning Activity.
-     */
-    protected <T> T getSystemService(final Class<T> serviceClass) {
-        return getActivity().getSystemService(serviceClass);
-    }
-
     /**
      * Returns the PackageManager from the owning Activity.
      */