Roll src/third_party/cros_system_api/ 46e2b4be3..b54e73475 (4 commits)

https://chromium.googlesource.com/chromiumos/platform2/system_api.git/+log/46e2b4be31c7..b54e73475dd0

$ git log 46e2b4be3..b54e73475 --date=short --no-merges --format='%ad %ae %s'
2018-10-30 semenzato system_api: generate Go bindings for MetricsEvent
2018-10-30 dverkamp system_api: concierge: add DISK_TYPE_AUTO value
2018-10-26 norvez system_api: remove BiometricsManager constants
2018-10-25 iby system_api: Add proto fields to support dependency message in uninstall

Created with:
  roll-dep src/third_party/cros_system_api

Change-Id: I242902eea0e44a6c07984d30602ea81a463a7b49
Reviewed-on: https://chromium-review.googlesource.com/c/1312567Reviewed-by: Nicholas Verne <nverne@chromium.org>
Commit-Queue: Daniel Verkamp <dverkamp@chromium.org>
Cr-Commit-Position: refs/heads/master@{#604941}

DEPS

@@ -670,7 +670,7 @@ deps = {
 
   # For Linux and Chromium OS.
   'src/third_party/cros_system_api': {
-      'url': Var('chromium_git') + '/chromiumos/platform2/system_api.git' + '@' + '46e2b4be31c717db64047079cce5c52cbda197ff',
+      'url': Var('chromium_git') + '/chromiumos/platform2/system_api.git' + '@' + 'b54e73475dd0ac786c006f3e027f30e6f782189e',
       'condition': 'checkout_linux',
   },