Never run errorprone on non-Chromium code.

build/config/android/internal_rules.gni

 # Copyright 2014 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import("//build/config/android/config.gni")
 
 assert(is_android)
 
 rebased_android_sdk = rebase_path(android_sdk, root_build_dir)
 rebased_android_sdk_root = rebase_path(android_sdk_root, root_build_dir)
@@ skipping 1015 matching lines @@
   if (defined(invoker.chromium_code)) {
     _chromium_code = invoker.chromium_code
   }
 
   _supports_android = true
   if (defined(invoker.supports_android)) {
     _supports_android = invoker.supports_android
   }
 
   _enable_errorprone = use_errorprone_java_compiler
-  if (defined(invoker.enable_errorprone)) {
+  if (!_chromium_code) {
+    _enable_errorprone = false
+  } else if (defined(invoker.enable_errorprone)) {
     _enable_errorprone = invoker.enable_errorprone
   }
 
   _manifest_entries = []
   if (defined(invoker.manifest_entries)) {
     _manifest_entries = invoker.manifest_entries
   }
 
   _srcjar_deps = []
   if (defined(invoker.srcjar_deps)) {
@@ skipping 568 matching lines @@
     ]
     args = [
       "--depfile",
       rebase_path(depfile, root_build_dir),
       "--script-output-path",
       rebase_path(generated_script, root_build_dir),
     ]
     args += test_runner_args
   }
 }