Remove tools/gritsettings

This directory is no longer needed after migrating from GYP to GN.

BUG=webrtc:5006
TBR=charujain@webrtc.org

Review-Url: https://codereview.webrtc.org/2595443002 .
Cr-Commit-Position: refs/heads/master@{#15696}

tools/gritsettings/README

@@ -1,7 +0,0 @@
-This is a dummy configuration file to workaround the assumption of the grit
-resource file being located here in the Chromium build toolchain.
-
-This is only needed for our Android native tests to be able to include the
-build/apk_test.gypi GYP file and depend on the
-<(DEPTH)/testing/android/native_test.gyp:native_test_native_code target in
-Chromium.

tools/gritsettings/resource_ids

@@ -1,15 +0,0 @@
-# Copyright (c) 2015 The WebRTC project authors. All Rights Reserved.
-#
-# Use of this source code is governed by a BSD-style license
-# that can be found in the LICENSE file in the root of the source
-# tree. An additional intellectual property rights grant can be found
-# in the file PATENTS.  All contributing project authors may
-# be found in the AUTHORS file in the root of the source tree.
-
-{
-  "SRCDIR": "../..",
-
-  "chromium/src/net/base/net_resources.grd": {
-    "includes": [4000],
-  },
-}