Roll src/third_party/cros_system_api/ 57bbe676e..670a0ff9f (2 commits)

https://chromium.googlesource.com/chromiumos/platform/system_api.git/+log/57bbe676efe5..670a0ff9f5a1

$ git log 57bbe676e..670a0ff9f --date=short --no-merges --format='%ad %ae %s'
2018-02-21 baileyberro smbprovider: add GetDeleteList protos
2018-03-01 dgreid vm_concierge: Add a command to list VM disk images

Created with:
  roll-dep src/third_party/cros_system_api

Change-Id: I9abfc78a3d258b061d52d4b66f9fe925ad38ae25
Reviewed-on: https://chromium-review.googlesource.com/953180Reviewed-by: Zentaro Kavanagh <zentaro@chromium.org>
Commit-Queue: Bailey Berro <baileyberro@chromium.org>
Cr-Commit-Position: refs/heads/master@{#541657}

DEPS

@@ -331,7 +331,7 @@ deps = {
 
   # For Linux and Chromium OS.
   'src/third_party/cros_system_api': {
-      'url': Var('chromium_git') + '/chromiumos/platform/system_api.git' + '@' + '57bbe676efe5f394395c123d713968d104e878bf',
+      'url': Var('chromium_git') + '/chromiumos/platform/system_api.git' + '@' + '670a0ff9f5a1d27b62e2a09d929f6e2ea32278ba',
       'condition': 'checkout_linux',
   },