releasetools: don't attempt to read fingerprint on unified devices

* You wont find this in the build.prop on these devices and this is
  how we handled them in previous versions

Change-Id: I56332c87916da1a1206980df0e7a6ca8a55f0e8e

diff --git a/tools/releasetools/ota_from_target_files.py b/tools/releasetools/ota_from_target_files.py
index d1bd71e..008f687 100755 (executable)
--- a/tools/releasetools/ota_from_target_files.py
+++ b/tools/releasetools/ota_from_target_files.py
@@ -492,6 +492,8 @@ def GetOemProperty(name, oem_props, oem_dict, info_dict):
 
 
 def CalculateFingerprint(oem_props, oem_dict, info_dict):
+  if OPTIONS.override_prop:
+    return GetBuildProp("ro.build.date.utc", info_dict)
   if oem_props is None:
     return GetBuildProp("ro.build.fingerprint", info_dict)
   return "%s/%s/%s:%s" % (