When building android_webview_unittests_apk target

ninja gave this warning which seems relevant:
ninja: warning: multiple rules generate bin/install_unittests_apk_incremental. builds involving this target will not be correct; continuing anyway [-w dupbuild=warn]

My args.gn:
target_os = "android"
target_cpu = "arm"
dcheck_always_on = true
is_debug = false
is_component_build = true
is_clang = true
symbol_level = 1
system_webview_package_name = "com.google.android.webview"

use_goma = false