Clean up usage of InvalidSyntax exception

src/flake8/exceptions.py

@@ -36,12 +36,17 @@ class InvalidSyntax(Flake8Exception):
 
     def __init__(self, *args, **kwargs):
         """Initialize our InvalidSyntax exception."""
-        self.original_exception = exc = kwargs.pop('exception')
-        self.error_message = str(exc) if exc is not None else ''
+        exception = kwargs.pop('exception', None)
+        self.original_exception = exception
+        self.error_message = str(exception)
         self.error_code = 'E902'
         self.line_number = 1
         self.column_number = 0
-        super(InvalidSyntax, self).__init__(*args, **kwargs)
+        super(InvalidSyntax, self).__init__(
+            self.error_message,
+            *args,
+            **kwargs
+        )
 
 
 class PluginRequestedUnknownParameters(Flake8Exception):

src/flake8/processor.py

@@ -247,7 +247,7 @@ class FileProcessor(object):
         # course, I'm going to be unsurprised to be proven wrong at a later
         # date.
         except tokenize.TokenError as exc:
-            raise exceptions.InvalidSyntax(str(exc), exception=exc)
+            raise exceptions.InvalidSyntax(exception=exc)
 
     def line_for(self, line_number):
         """Retrieve the physical line at the specified line number."""