Bluetooth SDP autotest: Bluetooth Tester to support Service Search Attribute

This CL adds Service Search Attribute Request method to BluetoothTester and
BluetoothTesterXmlRpcDelegate classes.

BUG=chromium:416168
TEST=pylint; use methods on stumpy and peppy

Change-Id: Idb8adfe35424c9697fab5ed9dd72c704da56f272
Reviewed-on: https://chromium-review.googlesource.com/219886
Tested-by: Artem Rakhov <arakhov@chromium.org>
Reviewed-by: Michael Janssen <jamuraa@chromium.org>
Reviewed-by: Arman Uguray <armansito@chromium.org>
Commit-Queue: Artem Rakhov <arakhov@chromium.org>
diff --git a/server/cros/bluetooth/bluetooth_tester.py b/server/cros/bluetooth/bluetooth_tester.py
index 2becb3e..d1ee919 100644
--- a/server/cros/bluetooth/bluetooth_tester.py
+++ b/server/cros/bluetooth/bluetooth_tester.py
@@ -168,6 +168,26 @@
                                                      invalid_request)
 
 
+    def service_search_attribute_request(self, uuids, max_attr_byte_count,
+                                         attr_ids, preferred_size=32):
+        """Send a Service Search Attribute Request
+
+        @param uuids: list of UUIDs (as integers) to look for.
+        @param max_attr_byte_count: maximum number of bytes of attribute data to
+               be returned in the response to this request.
+        @param attr_ids: a list, where each element is either an attribute ID
+               or a range of attribute IDs.
+        @param preferred_size: Preffered size of UUIDs in bits (16, 32, or 128).
+
+        @return list of found attributes IDs and their values or Error Code
+
+        """
+        return self._proxy.service_search_attribute_request(uuids,
+                                                            max_attr_byte_count,
+                                                            attr_ids,
+                                                            preferred_size)
+
+
 def create_host_from(device_host):
     """Creates a host object for the Tester associated with a DUT.