android envsetup: Stop exporting ANDROID_NDK_ROOT.

build/android/envsetup.sh

 #!/bin/bash
 # Copyright (c) 2012 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.
 
 # Sets up environment for building Chromium on Android.
 
 # Make sure we're being sourced (possibly by another script). Check for bash
 # since zsh sets $0 when sourcing.
 if [[ -n "$BASH_VERSION" && "${BASH_SOURCE:-$0}" == "$0" ]]; then
@@ skipping 30 matching lines @@
   # directory, "${CURRENT_DIR/"${CHROME_SRC}"/}" will be "".
   # Otherwise, it will equal to "${CURRENT_DIR}"
   echo "Warning: Current directory is out of CHROME_SRC, it may not be \
 the one you want."
   echo "${CHROME_SRC}"
 fi
 
 # Allow the caller to override a few environment variables. If any of them is
 # unset, we default to a sane value that's known to work. This allows for
 # experimentation with a custom SDK.
-if [[ -z "${ANDROID_NDK_ROOT}" || ! -d "${ANDROID_NDK_ROOT}" ]]; then
-  export ANDROID_NDK_ROOT="${CHROME_SRC}/third_party/android_tools/ndk/"
-fi
 if [[ -z "${ANDROID_SDK_ROOT}" || ! -d "${ANDROID_SDK_ROOT}" ]]; then
   export ANDROID_SDK_ROOT="${CHROME_SRC}/third_party/android_tools/sdk/"
 fi
 
 # Add Android SDK tools to system path.
 export PATH=$PATH:${ANDROID_SDK_ROOT}/tools
 export PATH=$PATH:${ANDROID_SDK_ROOT}/platform-tools
 
 # Add Chromium Android development scripts to system path.
 # Must be after CHROME_SRC is set.
 export PATH=$PATH:${CHROME_SRC}/build/android
 
 if [[ -n "$CHROME_ANDROID_OFFICIAL_BUILD" ]]; then
   # These defines are used by various chrome build scripts to tag the binary's
   # version string as 'official' in linux builds (e.g. in
   # chrome/trunk/src/chrome/tools/build/version.py).
   export OFFICIAL_BUILD=1
   export CHROMIUM_BUILD="_google_chrome"
   export CHROME_BUILD_TYPE="_official"
 fi
 
 # Performs a gyp_chromium run to convert gyp->Makefile for android code.
 android_gyp() {
   # This is just a simple wrapper of gyp_chromium, please don't add anything
   # in this function.
   "${CHROME_SRC}/build/gyp_chromium" --depth="${CHROME_SRC}" --check "$@"
 }