Remove "woosh" SOUND_START on lockscreen

Bug: 17178281
Change-Id: I76f010e66fa43d15ddbdc551d99e4bf3ab20f7b7
diff --git a/src/com/android/nfc/NfcService.java b/src/com/android/nfc/NfcService.java
index e5beb75..2fa9839 100755
--- a/src/com/android/nfc/NfcService.java
+++ b/src/com/android/nfc/NfcService.java
@@ -1617,8 +1617,10 @@
                             break;
                         }
                     }
-                    if (readerParams == null ||
-                            (readerParams.flags & NfcAdapter.FLAG_READER_NO_PLATFORM_SOUNDS) == 0) {
+
+                    boolean playSound = readerParams == null ||
+                        (readerParams.flags & NfcAdapter.FLAG_READER_NO_PLATFORM_SOUNDS) == 0;
+                    if (mScreenState == ScreenStateHelper.SCREEN_STATE_ON_UNLOCKED && playSound) {
                         playSound(SOUND_START);
                     }
                     if (tag.getConnectedTechnology() == TagTechnology.NFC_BARCODE) {
diff --git a/src/com/android/nfc/ScreenStateHelper.java b/src/com/android/nfc/ScreenStateHelper.java
index e7494a3..b044c28 100644
--- a/src/com/android/nfc/ScreenStateHelper.java
+++ b/src/com/android/nfc/ScreenStateHelper.java
@@ -6,8 +6,6 @@
 
 /**
  * Helper class for determining the current screen state for NFC activities.
- *
- * @hide
  */
 class ScreenStateHelper {