Fix master build. WirelessSettings is a fragment in master.

Change-Id: I9ad1104605558859d90dd1ecc083e9ef35bf3fa0
diff --git a/src/com/android/settings/WirelessSettings.java b/src/com/android/settings/WirelessSettings.java
index 5322555..e46707d 100644
--- a/src/com/android/settings/WirelessSettings.java
+++ b/src/com/android/settings/WirelessSettings.java
@@ -127,7 +127,7 @@
         }
 
         // Remove NFC if its not available
-        if (NfcAdapter.getDefaultAdapter(this) == null) {
+        if (NfcAdapter.getDefaultAdapter(activity) == null) {
             getPreferenceScreen().removePreference(nfc);
         }