Add presubmit=no and werror=no flags to Makefile

tools/presubmit.py

 #!/usr/bin/env python
 #
 # Copyright 2011 the V8 project authors. All rights reserved.
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are
 # met:
 #
 #     * Redistributions of source code must retain the above copyright
 #       notice, this list of conditions and the following disclaimer.
 #     * Redistributions in binary form must reproduce the above
@@ skipping 193 matching lines @@
     if len(files) == 0:
       print 'No changes in files detected. Skipping cpplint check.'
       return True
 
     filt = '-,' + ",".join(['+' + n for n in ENABLED_LINT_RULES])
     command = ['cpplint.py', '--filter', filt] + join(files)
     local_cpplint = join(path, "tools", "cpplint.py")
     if exists(local_cpplint):
       command = ['python', local_cpplint, '--filter', filt] + join(files)
 
-    process = subprocess.Popen(command, stderr=subprocess.PIPE)
+    try:
+      process = subprocess.Popen(command, stderr=subprocess.PIPE)
+    except:
+      print('Error running cpplint.py. Please make sure you have depot_tools' +
+            ' in your $PATH. Lint check skipped.')
+      return True
     LINT_ERROR_PATTERN = re.compile(r'^(.+)[:(]\d+[:)]')
     while True:
       out_line = process.stderr.readline()
       if out_line == '' and process.poll() != None:
         break
       sys.stderr.write(out_line)
       m = LINT_ERROR_PATTERN.match(out_line)
       if m:
         good_files_cache.RemoveFile(m.group(1))
 
@@ skipping 118 matching lines @@
   print "Running copyright header and trailing whitespaces check..."
   success = SourceProcessor().Run(workspace) and success
   if success:
     return 0
   else:
     return 1
 
 
 if __name__ == '__main__':
   sys.exit(Main())