Remove several unneeded modules from webkitpy.common.

Tools/Scripts/webkitpy/common/thread/messagepump.py

-# Copyright (c) 2010 Google Inc. All rights reserved.
-#
-# Redistribution and use in source and binary forms, with or without
-# modification, are permitted provided that the following conditions are
-# met:
-#
-#     * Redistributions of source code must retain the above copyright
-# notice, this list of conditions and the following disclaimer.
-#     * Redistributions in binary form must reproduce the above
-# copyright notice, this list of conditions and the following disclaimer
-# in the documentation and/or other materials provided with the
-# distribution.
-#     * Neither the name of Google Inc. nor the names of its
-# contributors may be used to endorse or promote products derived from
-# this software without specific prior written permission.
-#
-# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-
-
-class MessagePumpDelegate(object):
-    def schedule(self, interval, callback):
-        raise NotImplementedError, "subclasses must implement"
-
-    def message_available(self, message):
-        raise NotImplementedError, "subclasses must implement"
-
-    def final_message_delivered(self):
-        raise NotImplementedError, "subclasses must implement"
-
-
-class MessagePump(object):
-    interval = 10 # seconds
-
-    def __init__(self, delegate, message_queue):
-        self._delegate = delegate
-        self._message_queue = message_queue
-        self._schedule()
-
-    def _schedule(self):
-        self._delegate.schedule(self.interval, self._callback)
-
-    def _callback(self):
-        (messages, is_running) = self._message_queue.take_all()
-        for message in messages:
-            self._delegate.message_available(message)
-        if not is_running:
-            self._delegate.final_message_delivered()
-            return
-        self._schedule()