Version: Tip of master
OS: Android

What steps will reproduce the problem?
(1) Build an apk target with a proguard config

What is the expected output?
[1/1] Regenerating ninja files
<Build starts>

What do you see instead?
[1/1] Regenerating ninja files
ERROR at //build/config/android/rules.gni:2319:9: Replacing nonempty list.
        proguard_configs = invoker.proguard_configs
        ^---------------
This overwrites a previously-defined nonempty list (length 1).
See //amazon/mypath/BUILD.gn:156:24: for previous definition
    proguard_configs = [ "//amazon/mypath/java/proguard.flags" ]
                       ^----------------------------------------------
with another one (length 1). Did you mean "+=" to append instead? If you
really want to do this, do
  proguard_configs = []
before reassigning.


Please use labels and text to provide additional information.