Add a fallback for sys.stdout.encoding uses

In some environments (e.g. nosetest), sys.stdout.encoding can be None.
Add a fallback to handle these cases.

devlib/utils/android.py

@@ -152,7 +152,7 @@ class ApkInfo(object):
         try:
             output = subprocess.check_output(command, stderr=subprocess.STDOUT)
             if sys.version_info[0] == 3:
-                output = output.decode(sys.stdout.encoding, 'replace')
+                output = output.decode(sys.stdout.encoding or 'utf-8', 'replace')
         except subprocess.CalledProcessError as e:
             raise HostError('Error parsing APK file {}. `aapt` says:\n{}'
                             .format(apk_path, e.output))

devlib/utils/ssh.py

@@ -280,7 +280,7 @@ class SshConnection(object):
         # the regex removes line breaks potential introduced when writing
         # command to shell.
         if sys.version_info[0] == 3:
-            output = process_backspaces(self.conn.before.decode(sys.stdout.encoding, 'replace'))
+            output = process_backspaces(self.conn.before.decode(sys.stdout.encoding or 'utf-8', 'replace'))
         else:
             output = process_backspaces(self.conn.before)
         output = re.sub(r'\r([^\n])', r'\1', output)

devlib/utils/types.py

@@ -153,11 +153,11 @@ if sys.version_info[0] == 3:
         if isinstance(value, regex_type):
             if isinstance(value.pattern, bytes):
                 return value
-            return re.compile(value.pattern.encode(sys.stdout.encoding),
+            return re.compile(value.pattern.encode(sys.stdout.encoding or 'utf-8'),
                               value.flags & ~re.UNICODE)
         else:
             if isinstance(value, str):
-                value = value.encode(sys.stdout.encoding)
+                value = value.encode(sys.stdout.encoding or 'utf-8')
             return re.compile(value)
 else:
     def regex(value):

devlib/utils/version.py

@@ -25,6 +25,6 @@ def get_commit():
     if p.returncode:
         return None
     if sys.version_info[0] == 3 and isinstance(std, bytes):
-        return std[:8].decode(sys.stdout.encoding, 'replace')
+        return std[:8].decode(sys.stdout.encoding or 'utf-8', 'replace')
     else:
         return std[:8]