fix the bug of opening the file with the bytes can't be decoded to 'utf-8'

[yogurfrul]

Summary

fix the bug as blow:

ip- - [28/May/2017 17:16:23] "GET /TestDraft.cpp HTTP/1.1" 200 -

Exception happened during processing of request from ('ip', 56600)
Traceback (most recent call last):

File "/usr/lib/python3.4/socketserver.py", line 305, in _handle_request_noblock
  self.process_request(request, client_address)
File "/usr/lib/python3.4/socketserver.py", line 331, in process_request
  self.finish_request(request, client_address)
File "/usr/lib/python3.4/socketserver.py", line 344, in finish_request
  self.RequestHandlerClass(request, client_address, self)
File "/usr/lib/python3.4/socketserver.py", line 673, in __init__
  self.handle()
File "/usr/lib/python3.4/http/server.py", line 398, in handle
  self.handle_one_request()
File "/usr/lib/python3.4/http/server.py", line 386, in handle_one_request
  method()
File "/home/workspace/coverage-report-server.py", line 165, in do_GET
  for line_no, line in enumerate(f, start=1)])
File "/home/workspace/coverage-report-server.py", line 162, in <listcomp>
  ["<span class='{cls}'>{line}&nbsp;</span>".format(
File "/usr/lib/python3.4/codecs.py", line 319, in decode
  (result, consumed) = self._buffer_decode(data, self.errors, final)

UnicodeDecodeError: 'utf-8' codec can't decode byte 0xb5 in position 4164: invalid start byte

[yogurfrul]

update the path of changed file

[yogurfrul]

any reviewer here? My commit has been hold on 1 year!!!

[sylvestre.ledru]

Sorry, I am not a good reviewer for this file

[yogurfrul]

another two years passed~~~

llvm/trunk/tools/sancov/coverage-report-server.py

 
             linemap = self.symcov_data.compute_linemap(filename)
 
-            with open(filepath, 'r') as f:
+            with open(filepath, 'r', encoding='utf-8', errors='replace') as f:
                 content = "\n".join(
                         ["<span class='{cls}'>{line}&nbsp;</span>".format(
                             line=html.escape(line.rstrip()),