[core/camera]Update camera_android.py; fixes camera for Python 3

[gbm001]

In Python 3, the buffer needs to an explicit bytestring rather than a string; hence changing:
buf = '\x00' * self._bufsize
to
buf = b'\x00' * self._bufsize

Fixes various issues:
in Kivy #5939
and in associated garden project ZbarCam kivy-garden/garden.zbarcam#13

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[tito]

Is this still working with Python 2? I mean did you tried?

[gbm001]

I haven't because I haven't got a Python 2 environment set up to test it (I am very new to Kivy). However, it shouldn't make any difference in Python 2.6 as b'xxxxx' is completely identical to 'xxxxx' in Python 2. It will cause a SyntaxError in Python 2.5 as the syntax was introduced in 2.6, but I believe Kivy only supports 2.7+?

(strictly speaking the only differences are that if you have used from __future__ import unicode_literals it will reverse that, and that if you do 2to3 on your source code it will leave it as a bytestring rather than converting it to a Unicode string).

[welcome]

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[tito]

@gbm001 Thanks you!

[einav888]

I checked the camera_android.py file and it already was: buf = b'\x00' * self._bufsize
I'm trying to run this -> https://kivy.org/doc/stable/examples/gen__camera__main__py.html on Kivy Launcher. It runs perfectly on my computer, but crashes automatically on Kivy Launcher.
Do you have any idea what the reason could be?