Migrate DeviceUtils.ReadFile to adb_wrapper

tools/telemetry/telemetry/core/forwarders/android_forwarder.py

Index: tools/telemetry/telemetry/core/forwarders/android_forwarder.py
diff --git a/tools/telemetry/telemetry/core/forwarders/android_forwarder.py b/tools/telemetry/telemetry/core/forwarders/android_forwarder.py
index c5ef45d29fab7763b7e58e8d803b28d315d90230..19f5132f3cf0b7659b5bb9fadb1a63b0920ebe15 100644
--- a/tools/telemetry/telemetry/core/forwarders/android_forwarder.py
+++ b/tools/telemetry/telemetry/core/forwarders/android_forwarder.py
@@ -231,7 +231,7 @@ class AndroidRndisConfigurator(object):
     """Returns the name of the host-side network interface."""
     interface_list = self._EnumerateHostInterfaces()
     ether_address = self._device.ReadFile(
-        '%s/f_rndis/ethaddr' % self._RNDIS_DEVICE)[0]
+        '%s/f_rndis/ethaddr' % self._RNDIS_DEVICE).strip()
     interface_name = None
     for line in interface_list:
       if not line.startswith((' ', '\t')):
@@ -322,7 +322,7 @@ doit &
     self._device.RunShellCommand('rm %s.log' % script_prefix)
     self._device.RunShellCommand('. %s.sh' % script_prefix)
     self._WaitForDevice()
-    result = self._device.ReadFile('%s.log' % script_prefix)
+    result = self._device.ReadFile('%s.log' % script_prefix).splitlines()
     assert any('DONE' in line for line in result), 'RNDIS script did not run!'
 
   def _CheckEnableRndis(self, force):