Add authorize_adb_keys step that will add host key to device.

scripts/slave/recipe_modules/chromium_android/api.py

 # Copyright 2013 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import os
 import re
 import urllib
 
 from infra.libs.infra_types import freeze
 from slave import recipe_api
@@ skipping 275 matching lines @@
 
   def spawn_logcat_monitor(self):
     self.m.step(
         'spawn_logcat_monitor',
         [self.m.path['build'].join('scripts', 'slave', 'daemonizer.py'),
          '--', self.c.cr_build_android.join('adb_logcat_monitor.py'),
          self.m.chromium.c.build_dir.join('logcat')],
         env=self.m.chromium.get_env(),
         infra_step=True)
 
+
+  def authorize_adb_devices(self):
+    script = self.m.path['build'].join('scripts', 'slave', 'android',
+                                    'authorize_adb_devices.py')
+    args = ['--adb-path', self.m.path['checkout'].join('third_party',
+                               'android_tools', 'sdk', 'platform-tools', 'adb')]
+    return self.m.python('authorize_adb_devices', script, args, infra_step=True,
+                       env=self.m.chromium.get_env())
+
+
   def detect_and_setup_devices(self, restart_usb=False, skip_wipe=False,
                                disable_location=False, min_battery_level=None,
                                disable_network=False, disable_java_debug=False,
                                reboot_timeout=None):
+    self.authorize_adb_devices()
     self.device_status_check(restart_usb=restart_usb)
     self.provision_devices(
       skip_wipe=skip_wipe, disable_location=disable_location,
       min_battery_level=min_battery_level, disable_network=disable_network,
       disable_java_debug=disable_java_debug, reboot_timeout=reboot_timeout)
 
   def device_status_check(self, restart_usb=False, **kwargs):
     args = ['--json-output', self.m.json.output()]
     if restart_usb:
       args += ['--restart-usb']
@@ skipping 306 matching lines @@
               os.remove(report)
          """,
          args=[self.m.path['checkout'].join('out',
                                             self.m.chromium.c.BUILD_CONFIG,
                                             'test_logs',
                                             '*.log')],
     )
 
   def common_tests_setup_steps(self, perf_setup=False):
     self.spawn_logcat_monitor()
+    self.authorize_adb_devices()
     self.device_status_check()
     if perf_setup:
       kwargs = {
           'min_battery_level': 95,
           'disable_network': True,
           'disable_java_debug': True}
     else:
       kwargs = {}
     self.provision_devices(**kwargs)
 
@@ skipping 115 matching lines @@
       return step_result
     except self.m.step.StepFailure as f:
       step_result = f.result
       raise
     finally:
       if (step_result.retcode == EXIT_CODES['error']):
         step_result.presentation.status = self.m.step.FAILURE
       elif (step_result.retcode == EXIT_CODES['infra']):
         step_result.presentation.status = self.m.step.EXCEPTION
       elif (step_result.retcode == EXIT_CODES['warning']):
-        step_result.presentation.status = self.m.step.WARNING
+        step_result.presentation.status = self.m.step.WARNING