Use depot_tools to provide ninja binary and cpplint.

script/build.py

@@ -7,13 +7,20 @@ import sys
 
 
 CONFIGURATIONS = ['Release', 'Debug']
+SOURCE_ROOT = os.path.dirname(os.path.dirname(__file__))
 
 
 def main():
+  os.chdir(SOURCE_ROOT)
+
+  ninja = os.path.join('vendor', 'depot_tools', 'ninja')
+  if sys.platform == 'win32':
+    ninja += '.exe'
+
   args = parse_args()
   for config in args.configuration:
     build_path = os.path.join('out', config)
-    subprocess.call(['ninja', '-C', build_path])
+    subprocess.call([ninja, '-C', build_path])
 
 
 def parse_args():

script/cpplint.py

@@ -6,6 +6,7 @@ import subprocess
 import sys
 
 OBJC_HEADERS = [
+  'app/win/resource.h',
   'browser/atom_event_processing_window.h',
   'browser/atom_application_mac.h',
   'browser/atom_application_delegate_mac.h',
@@ -36,7 +37,7 @@ def list_files(directories, filters):
 
 
 def call_cpplint(files):
-  cpplint = os.path.join(SOURCE_ROOT, 'vendor', 'cpplint.py')
+  cpplint = os.path.join(SOURCE_ROOT, 'vendor', 'depot_tools', 'cpplint.py')
   rules = '--filter=-build/header_guard,-build/include_what_you_use'
   subprocess.call([sys.executable, cpplint, rules] + files)