title: No package 'xkbfile' found when build vscode on Ubuntu
body: <p>I'm building VS Code from source on Ubuntu 18.04.2 LTS.
  While running </p>
  
  <pre><code>yarn run watch
  </code></pre>
  
  <p>as instructed on <a href="https://github.com/Microsoft/vscode/wiki/How-to-Contribute#build-and-run" rel="noreferrer">https://github.com/Microsoft/vscode/wiki/How-to-Contribute#build-and-run</a> and got following error.</p>
  
  <pre><code>Error: Cannot find module 'gulp-watch'
      at Function.Module._resolveFilename (module.js:547:15)
      at Function.Module._load (module.js:474:25)
      at Module.require (module.js:596:17)
      at require (internal/module.js:11:18)
      at Object.&lt;anonymous&gt; (/home/title/workspace/vscode/build/lib/watch/index.js:23:68)
      at Module._compile (module.js:652:30)
      at Object.Module._extensions..js (module.js:663:10)
      at Module.load (module.js:565:32)
      at tryModuleLoad (module.js:505:12)
      at Function.Module._load (module.js:497:3)
  error Command failed with exit code 1.
  </code></pre>
  
  <p>So, I tried to install gulp-watch by executing <code>yarn add gulp-watch --no-save</code> and got following error</p>
  
  <pre><code>error /home/title/workspace/vscode/node_modules/native-keymap: Command failed.
  Exit code: 1
  Command: node-gyp rebuild
  Arguments: 
  Directory: /home/title/workspace/vscode/node_modules/native-keymap
  Output:
  gyp info it worked if it ends with ok
  gyp info using node-gyp@3.6.2
  gyp info using node@8.10.0 | linux | x64
  gyp info spawn /usr/bin/python2
  gyp info spawn args [ '/usr/share/node-gyp/gyp/gyp_main.py',
  gyp info spawn args   'binding.gyp',
  gyp info spawn args   '-f',
  gyp info spawn args   'make',
  gyp info spawn args   '-I',
  gyp info spawn args   '/home/title/workspace/vscode/node_modules/native-keymap/build/config.gypi',
  gyp info spawn args   '-I',
  gyp info spawn args   '/usr/share/node-gyp/addon.gypi',
  gyp info spawn args   '-I',
  gyp info spawn args   '/home/title/.node-gyp/iojs-3.1.8/common.gypi',
  gyp info spawn args   '-Dlibrary=shared_library',
  gyp info spawn args   '-Dvisibility=default',
  gyp info spawn args   '-Dnode_root_dir=/home/title/.node-gyp/iojs-3.1.8',
  gyp info spawn args   '-Dnode_gyp_dir=/usr/share/node-gyp',
  gyp info spawn args   '-Dnode_lib_file=/home/title/.node-gyp/iojs-3.1.8/&lt;(target_arch)/iojs.lib',
  gyp info spawn args   '-Dmodule_root_dir=/home/title/workspace/vscode/node_modules/native-keymap',
  gyp info spawn args   '-Dnode_engine=v8',
  gyp info spawn args   '--depth=.',
  gyp info spawn args   '--no-parallel',
  gyp info spawn args   '--generator-output',
  gyp info spawn args   'build',
  gyp info spawn args   '-Goutput_dir=.' ]
  Package xkbfile was not found in the pkg-config search path.
  Perhaps you should add the directory containing `xkbfile.pc'
  to the PKG_CONFIG_PATH environment variable
  No package 'xkbfile' found
  gyp: Call to 'pkg-config x11 xkbfile --libs' returned exit status 1 while in binding.gyp. while trying to load binding.gyp
  gyp ERR! configure error 
  gyp ERR! stack Error: `gyp` failed with exit code: 1
  gyp ERR! stack     at ChildProcess.onCpExit (/usr/share/node-gyp/lib/configure.js:340:16)
  gyp ERR! stack     at emitTwo (events.js:126:13)
  gyp ERR! stack     at ChildProcess.emit (events.js:214:7)
  gyp ERR! stack     at Process.ChildProcess._handle.onexit (internal/child_process.js:198:12)
  gyp ERR! System Linux 4.15.0-47-generic
  gyp ERR! command "/usr/bin/node" "/usr/bin/node-gyp" "rebuild"
  gyp ERR! cwd /home/title/workspace/vscode/node_modules/native-keymap
  </code></pre>
  
  <p>What interested me is <code>No package 'xkbfile' found</code> message, but didn't find much related to xkbfile.</p>
  
  <p>How do I get pass this?</p>
  
  <p>Thanks</p>