Migrate test_utils from acts to acts_contrib

This change will allow the ACTS framework to be packaged independently
of its test_utils. This facilitates the usage of ACTS within test suites
outside of tools/test/connectivity.

Re-submission of ag/13029169.
This reverts commit a4913cd4087bb09bf192de6ef819657aa6e082bd.

Reason for revert: Submit once references in acts_power are fixed.

Change-Id: I2d60f8ccaf936a80820a7b4387c23bbce1293dcf
diff --git a/acts_tests/acts_contrib/test_utils/net/connectivity_test_utils.py b/acts_tests/acts_contrib/test_utils/net/connectivity_test_utils.py
new file mode 100644
index 0000000..d35fe04
--- /dev/null
+++ b/acts_tests/acts_contrib/test_utils/net/connectivity_test_utils.py
@@ -0,0 +1,119 @@
+#
+#   Copyright 2018 - The Android Open Source Project
+#
+#   Licensed under the Apache License, Version 2.0 (the "License");
+#   you may not use this file except in compliance with the License.
+#   You may obtain a copy of the License at
+#
+#       http://www.apache.org/licenses/LICENSE-2.0
+#
+#   Unless required by applicable law or agreed to in writing, software
+#   distributed under the License is distributed on an "AS IS" BASIS,
+#   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#   See the License for the specific language governing permissions and
+#   limitations under the License.
+
+from acts import asserts
+from acts_contrib.test_utils.net import connectivity_const as cconst
+from queue import Empty
+
+def _listen_for_keepalive_event(ad, key, msg, ka_event):
+    """Listen for keepalive event and return status
+
+    Args:
+        ad: DUT object
+        key: keepalive key
+        msg: Error message
+        event: Keepalive event type
+    """
+    ad.droid.socketKeepaliveStartListeningForEvent(key, ka_event)
+    try:
+        event = ad.ed.pop_event("SocketKeepaliveCallback")
+        status = event["data"]["socketKeepaliveEvent"] == ka_event
+    except Empty:
+        asserts.fail(msg)
+    finally:
+        ad.droid.socketKeepaliveStopListeningForEvent(key, ka_event)
+    if ka_event != "Started":
+        ad.droid.removeSocketKeepaliveReceiverKey(key)
+    if status:
+        ad.log.info("'%s' keepalive event successful" % ka_event)
+    return status
+
+def start_natt_socket_keepalive(ad, udp_encap, src_ip, dst_ip, interval = 10):
+    """Start NATT SocketKeepalive on DUT
+
+    Args:
+        ad: DUT object
+        udp_encap: udp_encap socket key
+        src_ip: IP addr of the client
+        dst_ip: IP addr of the keepalive server
+        interval: keepalive time interval
+    """
+    ad.log.info("Starting Natt Socket Keepalive")
+    key = ad.droid.startNattSocketKeepalive(udp_encap, src_ip, dst_ip, interval)
+    msg = "Failed to receive confirmation of starting natt socket keeaplive"
+    status = _listen_for_keepalive_event(ad, key, msg, "Started")
+    return key if status else None
+
+def start_tcp_socket_keepalive(ad, socket, time_interval = 10):
+    """Start TCP socket keepalive on DUT
+
+    Args:
+        ad: DUT object
+        socket: TCP socket key
+        time_interval: Keepalive time interval
+    """
+    ad.log.info("Starting TCP Socket Keepalive")
+    key = ad.droid.startTcpSocketKeepalive(socket, time_interval)
+    msg = "Failed to receive confirmation of starting tcp socket keeaplive"
+    status = _listen_for_keepalive_event(ad, key, msg, "Started")
+    return key if status else None
+
+def socket_keepalive_error(ad, key):
+    """Verify Error callback
+
+    Args:
+        ad: DUT object
+        key: Keepalive key
+    """
+    ad.log.info("Verify Error callback on keepalive: %s" % key)
+    msg = "Failed to receive confirmation of Error callback"
+    return _listen_for_keepalive_event(ad, key, msg, "Error")
+
+def socket_keepalive_data_received(ad, key):
+    """Verify OnDataReceived callback
+
+    Args:
+        ad: DUT object
+        key: Keepalive key
+    """
+    ad.log.info("Verify OnDataReceived callback on keepalive: %s" % key)
+    msg = "Failed to receive confirmation of OnDataReceived callback"
+    return _listen_for_keepalive_event(ad, key, msg, "OnDataReceived")
+
+def stop_socket_keepalive(ad, key):
+    """Stop SocketKeepalive on DUT
+
+    Args:
+        ad: DUT object
+        key: Keepalive key
+    """
+    ad.log.info("Stopping Socket keepalive: %s" % key)
+    ad.droid.stopSocketKeepalive(key)
+    msg = "Failed to receive confirmation of stopping socket keepalive"
+    return _listen_for_keepalive_event(ad, key, msg, "Stopped")
+
+def set_private_dns(ad, dns_mode, hostname=None):
+    """ Set private DNS mode on dut """
+    if dns_mode == cconst.PRIVATE_DNS_MODE_OFF:
+        ad.droid.setPrivateDnsMode(False)
+    else:
+        ad.droid.setPrivateDnsMode(True, hostname)
+
+    mode = ad.droid.getPrivateDnsMode()
+    host = ad.droid.getPrivateDnsSpecifier()
+    ad.log.info("DNS mode is %s and DNS server is %s" % (mode, host))
+    asserts.assert_true(dns_mode == mode and host == hostname,
+                        "Failed to set DNS mode to %s and DNS to %s" % \
+                        (dns_mode, hostname))