Change provision_devices.py to disable verity for remove webview on M

build/android/provision_devices.py

 #!/usr/bin/env python
 #
 # Copyright (c) 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.
 
 """Provisions Android devices with settings required for bots.
 
 Usage:
   ./provision_devices.py [-d <device serial number>]
@@ skipping 277 matching lines @@
   if options.disable_network:
     device_settings.ConfigureContentSettings(
         device, device_settings.NETWORK_DISABLED_SETTINGS)
 
   if options.disable_system_chrome:
     # The system chrome version on the device interferes with some tests.
     device.RunShellCommand(['pm', 'disable', 'com.android.chrome'],
                            check_return=True)
 
   if options.remove_system_webview:
-    if device.HasRoot():
-      # This is required, e.g., to replace the system webview on a device.
-      device.adb.Remount()
-      device.RunShellCommand(['stop'], check_return=True)
-      device.RunShellCommand(['rm', '-rf'] + _SYSTEM_WEBVIEW_PATHS,
-                             check_return=True)
-      device.RunShellCommand(['start'], check_return=True)
+    if any(device.PathExists(p) for p in _SYSTEM_WEBVIEW_PATHS):
+      logging.info('System WebView exists and needs to be removed')
+      if device.HasRoot():
+        # Disabled Marshmallow's Verity security feature
+        if device.build_version_sdk >= version_codes.MARSHMALLOW:
+          device.adb.DisableVerity()
+          device.Reboot()
+          device.WaitUntilFullyBooted()
+          device.EnableRoot()
+
+        # This is required, e.g., to replace the system webview on a device.
+        device.adb.Remount()
+        device.RunShellCommand(['stop'], check_return=True)
+        device.RunShellCommand(['rm', '-rf'] + _SYSTEM_WEBVIEW_PATHS,
+                               check_return=True)
+        device.RunShellCommand(['start'], check_return=True)
+      else:
+        logging.warning('Cannot remove system webview from a non-rooted device')
     else:
-      logging.warning('Cannot remove system webview from a non-rooted device')
+      logging.info('System WebView already removed')
 
   # Some device types can momentarily disappear after setting properties.
   device.adb.WaitForDevice()
 
 
 def _ConfigureLocalProperties(device, java_debug=True):
   """Set standard readonly testing device properties prior to reboot."""
   local_props = [
       'persist.sys.usb.config=adb',
       'ro.monkey=1',
@@ skipping 219 matching lines @@
       },
     }
 
   devil_chromium.Initialize(custom_deps=devil_custom_deps)
 
   return ProvisionDevices(args)
 
 
 if __name__ == '__main__':
   sys.exit(main())