native_client_sdk: Remove GetPreferredTryMasters from PRESUBMIT.

The masters and bots listed don't exists anymore.
GetPreferredTryMasters is used by git-cl try to pick what bots
to trigger. I want to remove support for it, since its not used
and increases maintenance costs.
Skipping presubmit because of unrelated pylint failures.

No-Presubmit: true
Change-Id: I3f539a2d08444fc1dd3851777aeb1b9a71407bd7
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2072643
Commit-Queue: Edward Lesmes <ehmaldonado@chromium.org>
Reviewed-by: Sam Clegg <sbc@chromium.org>
Cr-Commit-Position: refs/heads/master@{#745327}

native_client_sdk/PRESUBMIT.py

@@ -37,20 +37,3 @@ def CheckChangeOnUpload(input_api, output_api):
 
 def CheckChangeOnCommit(input_api, output_api):
   return CommonChecks(input_api, output_api)
-
-
-def GetPreferredTryMasters(project, change):
-  return {
-    'master.tryserver.chromium.linux': {
-      'linux_nacl_sdk': set(['defaulttests']),
-      'linux_nacl_sdk_build': set(['defaulttests']),
-    },
-    'master.tryserver.chromium.win': {
-      'win_nacl_sdk': set(['defaulttests']),
-      'win_nacl_sdk_build': set(['defaulttests']),
-    },
-    'master.tryserver.chromium.mac': {
-      'mac_nacl_sdk': set(['defaulttests']),
-      'mac_nacl_sdk_build': set(['defaulttests']),
-    }
-  }