[FIX] Error Reporting: open encode as unicode

[jerneju]

Issue

Description of changes

Includes

• Code changes
• Tests
• Documentation

[jerneju]

https://sentry.io/biolab/orange3/issues/204303618/

[codecov-io]

Codecov Report

Merging #2416 into master will increase coverage by 3.32%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #2416      +/-   ##
==========================================
+ Coverage    73.9%   77.22%   +3.32%     
==========================================
  Files         321      325       +4     
  Lines       55993    64896    +8903     
==========================================
+ Hits        41379    50118    +8739     
- Misses      14614    14778     +164

[janezd]

My first question after seeing this PR was --- why?

Is this needed because scheme_to_ows_stream saves as utf-8? Please provide better description of PRs: what they are fixing, how, what is needed to reproduce the bug (if applicable)... to make the reviewers' work easier.

[janezd]

Is this still WIP? Plus, can you answer the above question so we can proceed with the PR?

[jerneju]

I have not reproduced this bug yet, so now I am (temporarily?) closing this PR.

[ales-erjavec]

Run LC_ALL=C orange-canvas
Add some widget to the workflow, rename it to some non ascii name and trigger an exception (in some way):

-------------------------------------------------------------------------------
Error in sys.excepthook:
Traceback (most recent call last):
  File "/usr/local/Cellar/python3/3.5.2_3/Frameworks/Python.framework/Versions/3.5/lib/python3.5/unittest/mock.py", line 1157, in patched
    return func(*args, **keywargs)
  File "/Users/aleserjavec/workspace/orange3/Orange/canvas/application/errorreporting.py", line 229, in handle_exception
    data['_' + F.WIDGET_SCHEME] = f.read()
  File "/Users/aleserjavec/virtual/orange3/bin/../lib/python3.5/encodings/ascii.py", line 26, in decode
    return codecs.ascii_decode(input, self.errors)[0]
UnicodeDecodeError: 'ascii' codec can't decode byte 0xc4 in position 237: ordinal not in range(128)

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/Users/aleserjavec/workspace/orange3/Orange/canvas/application/outputview.py", line 228, in __call__
    self.handledException.emit(((exc_type, exc_value, tb), self._canvas))
SystemError: <built-in method emit of PyQt5.QtCore.pyqtBoundSignal object at 0x125cd9558> returned a result with an error set

[jerneju]

Now I reproduced this error, tested it and this fix works.