Add Javadoc for PollingFrame constructor

Bug: 329144913
Test: just javadoc
Merged-In: If731d3fe6ee045b6177923f31d3cb179062d046f
Change-Id: If731d3fe6ee045b6177923f31d3cb179062d046f
diff --git a/nfc/java/android/nfc/cardemulation/PollingFrame.java b/nfc/java/android/nfc/cardemulation/PollingFrame.java
index 7028c8f..af63a6e 100644
--- a/nfc/java/android/nfc/cardemulation/PollingFrame.java
+++ b/nfc/java/android/nfc/cardemulation/PollingFrame.java
@@ -174,6 +174,16 @@
                 && frame.getBoolean(KEY_POLLING_LOOP_TRIGGERED_AUTOTRANSACT);
     }
 
+    /**
+     * Constructor for Polling Frames.
+     *
+     * @param type the type of the frame
+     * @param data a byte array of the data contained in the frame
+     * @param gain the vendor-specific gain of the field
+     * @param timestamp the timestamp in millisecones
+     * @param triggeredAutoTransact whether or not this frame triggered the device to start a
+     * transaction automatically
+     */
     public PollingFrame(@PollingFrameType int type, @Nullable byte[] data,
             int gain, int timestamp, boolean triggeredAutoTransact) {
         mType = type;