GN WebView: make system_webview_apk work

android_webview/system_webview_apk_tmpl.gni

+# Copyright 2015 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")
+
+template("system_webview_apk_tmpl") {
+  android_apk(target_name) {
+    forward_variables_from(invoker, "*")
+
+    deps += [
+      "//android_webview:assets",
+      "//android_webview:libwebviewchromium",
+      "//base:base_java",
+    ]
+
+    shared_resources = true
+    native_libs = [ "libwebviewchromium.so" ]
+    native_lib_version_rule = "//build/util:chrome_version_json"
+    _native_lib_file =
+        rebase_path("$root_gen_dir/CHROME_VERSION.json", root_out_dir)
+    native_lib_version_arg = "@FileArg($_native_lib_file:full-quoted)"
+    extensions_to_not_compress = ".lpak,.pak,.bin,.dat"
+  }
+}