Make Linker.isUsed() static, and clean up the fallout.

content/shell/android/BUILD.gn

 # 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")
 import("//build/config/android/rules.gni")
 import("//build/module_args/v8.gni")
 import("//third_party/icu/config.gni")
 
 generate_jni("content_shell_jni_headers") {
@@ skipping 148 matching lines @@
     "//base:base_javatests",
     "//net/android:net_javatests",
   ]
   data_deps = [ ":content_shell_apk" ]
   apk_under_test = ":content_shell_apk"
   apk_name = "ContentShellTest"
   android_manifest = "javatests/AndroidManifest.xml"
   isolate_file = "../../content_shell_test_apk.isolate"
 }
 
-if (current_cpu != "x64" && current_cpu != "arm64") {
+if (current_cpu != "x64") {
   chromium_linker_test_manifest =
       "$target_gen_dir/linker_test_apk/AndroidManifest.xml"
 
   jinja_template("chromium_linker_test_manifest") {
     testonly = true
     input = "linker_test_apk/AndroidManifest.xml.jinja2"
     output = chromium_linker_test_manifest
   }
 
   android_resources("linker_resources") {
@@ skipping 48 matching lines @@
 
   # GYP: //content/content_tests.gypi:chromium_android_linker_test_jni_headers
   generate_jni("linker_test_jni_headers") {
     testonly = true
     jni_package = "content/shell"
     sources = [
       "linker_test_apk/src/org/chromium/chromium_linker_test_apk/LinkerTests.java",
     ]
   }
 }