PAN: Fix disconnect stuck issue during multi device use case.

Precondition:
Enable BT Tethering on peer devices

Use case:
1) DUT has been paired with 3 phones
2) After pair go to first device details
3) Enable Internet access to initiate PANU connection
4) After successful connection with first peer
5) Go to second devices details enable internet access
6) Repeat above steps multiple times

Observed result:
Received disconnected call back on the wrong(Connected) device.
So, in UI for disconnecting device, showing status as
Disconnecting until BT reset.

Fix:
During back to back calls of connect and disconnection
sometimes there is a chance of duplicate handles inside btpan_conn_t
So, retrieve btpan connection instance using bt address which is unique
instead of close handle, so that DUT always can send proper device during
connection state callback and to initiate proper cleanup during close connection.

CRs-Fixed: 2685265
Change-Id: If424e02ae67e6252fca8f5ad742543a6bb632114

bta/include/bta_pan_api.h

@@ -86,6 +86,7 @@ typedef struct {
 
 /* Event associated with BTA_PAN_CLOSE_EVT */
 typedef struct {
+  RawAddress bd_addr; /* BD address of peer device. */
   uint16_t handle; /* Handle associated with the connection. */
 } tBTA_PAN_CLOSE;
 

bta/pan/bta_pan_act.cc

@@ -550,6 +550,7 @@ void bta_pan_conn_close(tBTA_PAN_SCB* p_scb, tBTA_PAN_DATA* p_data) {
   BT_HDR* p_buf;
 
   bta_pan.close.handle = p_data->hdr.layer_specific;
+  bta_pan.close.bd_addr = p_scb->bd_addr;
 
   bta_sys_conn_close(BTA_ID_PAN, p_scb->app_id, p_scb->bd_addr);
 

btif/src/btif_pan.cc

@@ -621,17 +621,19 @@ static void bta_pan_callback_transfer(uint16_t event, char* p_param) {
     case BTA_PAN_OPEN_EVT: {
       btpan_connection_state_t state;
       bt_status_t status;
-      btpan_conn_t* conn = btpan_find_conn_handle(p_data->open.handle);
+      btpan_conn_t* conn;
 
       LOG_VERBOSE(LOG_TAG, "%s pan connection open status: %d", __func__,
                   p_data->open.status);
       if (p_data->open.status == BTA_PAN_SUCCESS) {
         state = BTPAN_STATE_CONNECTED;
         status = BT_STATUS_SUCCESS;
+        conn = btpan_find_conn_handle(p_data->open.handle);
         btpan_open_conn(conn, p_data);
       } else {
         state = BTPAN_STATE_DISCONNECTED;
         status = BT_STATUS_FAIL;
+        conn = btpan_find_conn_addr(p_data->open.bd_addr);
         btpan_cleanup_conn(conn);
       }
       /* debug("BTA_PAN_OPEN_EVT handle:%d, conn:%p",  p_data->open.handle,
@@ -647,7 +649,7 @@ static void bta_pan_callback_transfer(uint16_t event, char* p_param) {
     case BTA_PAN_CLOSE_EVT: {
       LOG_INFO(LOG_TAG, "%s event = BTA_PAN_CLOSE_EVT handle %d", __func__,
                p_data->close.handle);
-      btpan_conn_t* conn = btpan_find_conn_handle(p_data->close.handle);
+      btpan_conn_t* conn = btpan_find_conn_addr(p_data->close.bd_addr);
 
       if (conn && conn->handle >= 0) {
         int btpan_conn_local_role = bta_role_to_btpan(conn->local_role);