autotest: waive input_device probing for fleex

Since all tests share the same host_info_labels (especially cros
labels), we need to patch the control file to reflect the touch probing
waiver (crrev.com/i/3413990) for legacy release branch when the issue is
only fixed at recent branches.

BUG=b:178762107
TEST=test_that -b octopus "${R88_FLEEX_DUT}" tast.runtime-probe  # and
verify if the test passes.

Change-Id: If374a382f268cbf536f2611a45e623f31cdf1c9e
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/third_party/autotest/+/2658440
Commit-Queue: Clark Chung <ckclark@chromium.org>
Tested-by: Clark Chung <ckclark@chromium.org>
Reviewed-by: Shuhei Takahashi <nya@chromium.org>
diff --git a/server/site_tests/tast/control.runtime-probe b/server/site_tests/tast/control.runtime-probe
index 937fd28..9a3ba73 100644
--- a/server/site_tests/tast/control.runtime-probe
+++ b/server/site_tests/tast/control.runtime-probe
@@ -24,11 +24,22 @@
 import tempfile
 import yaml
 
+_INPUT_DEVICE_PREFIX = set([
+        'hwid_component:touchpad',
+        'hwid_component:touchscreen',
+        'hwid_component:stylus',
+])
+
 def run(machine):
     host = hosts.create_host(machine)
     with tempfile.NamedTemporaryFile(suffix='.yaml') as temp_file:
         host_info = host.host_info_store.get()
-        yaml.dump({"autotest_host_info_labels": json.dumps(host_info.labels)},
+        labels = host_info.labels
+
+        if 'model:fleex' in labels:
+            labels = [label for label in labels
+                      if label.split('/')[0] not in _INPUT_DEVICE_PREFIX]
+        yaml.dump({'autotest_host_info_labels': json.dumps(labels)},
                   stream=temp_file)
         job.run_test('tast',
                      host=host,