move zip template to a non-android-specific .gni file

build/config/zip.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.
+
+# Creates a zip archive of the inputs.
+# If base_dir is provided, the archive paths will be relative to it.
+template("zip") {
+  set_sources_assignment_filter([])
+  if (defined(invoker.testonly)) {
+    testonly = invoker.testonly
+  }
+
+  assert(defined(invoker.inputs))
+  assert(defined(invoker.output))
+
+  rebase_inputs = rebase_path(invoker.inputs, root_build_dir)
+  rebase_output = rebase_path(invoker.output, root_build_dir)
+  action(target_name) {
+    script = "//build/android/gn/zip.py"
+    depfile = "$target_gen_dir/$target_name.d"
+    inputs = invoker.inputs
+    outputs = [
+      depfile,
+      invoker.output,
+    ]
+    args = [
+      "--depfile",
+      rebase_path(depfile, root_build_dir),
+      "--inputs=$rebase_inputs",
+      "--output=$rebase_output",
+    ]
+    if (defined(invoker.base_dir)) {
+      args += [
+        "--base-dir",
+        rebase_path(invoker.base_dir, root_build_dir),
+      ]
+    }
+
+    if (defined(invoker.deps)) {
+      deps = invoker.deps
+    }
+    if (defined(invoker.public_deps)) {
+      public_deps = invoker.public_deps
+    }
+    if (defined(invoker.data_deps)) {
+      data_deps = invoker.data_deps
+    }
+
+    if (defined(invoker.visibility)) {
+      visibility = invoker.visibility
+    }
+  }
+}