ChromeDriver has pre-installed APK's, thus should not wipe during provisioning.

build/android/buildbot/bb_device_steps.py

Index: build/android/buildbot/bb_device_steps.py
diff --git a/build/android/buildbot/bb_device_steps.py b/build/android/buildbot/bb_device_steps.py
index 29a4add416408b9671ce1597fe2d96304b2fb6f9..de70d803a46fd6d03aabfc110dad48117789aa0b 100755
--- a/build/android/buildbot/bb_device_steps.py
+++ b/build/android/buildbot/bb_device_steps.py
@@ -412,6 +412,8 @@ def ProvisionDevices(options):
   provision_cmd = ['build/android/provision_devices.py', '-t', options.target]
   if options.auto_reconnect:
     provision_cmd.append('--auto-reconnect')
+  if options.skip_wipe:
+    provision_cmd.append('--skip-wipe')
   RunCmd(provision_cmd)
 
 
@@ -647,6 +649,8 @@ def GetDeviceStepsOptParser():
   parser.add_option(
       '--auto-reconnect', action='store_true',
       help='Push script to device which restarts adbd on disconnections.')
+  parser.add_option('--skip-wipe', action='store_true',
+                    help='Do not wipe devices during provisioning.')
   parser.add_option(
       '--logcat-dump-output',
       help='The logcat dump output will be "tee"-ed into this file')