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diff --git a/WebKitTools/Scripts/webkitpy/layout_tests/layout_package/metered_stream.py b/WebKitTools/Scripts/webkitpy/layout_tests/layout_package/metered_stream.py
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+++ b/WebKitTools/Scripts/webkitpy/layout_tests/layout_package/metered_stream.py
@@ -0,0 +1,96 @@
+#!/usr/bin/env python
+# Copyright (C) 2010 The Chromium Authors. 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 Chromium name 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.
+
+"""
+Package that implements a stream wrapper that has 'meters' as well as
+regular output. A 'meter' is a single line of text that can be erased
+and rewritten repeatedly, without producing multiple lines of output. It
+can be used to produce effects like progress bars.
+"""
+
+
+class MeteredStream:
+    """This class is a wrapper around a stream that allows you to implement
+    meters.
+
+    It can be used like a stream, but calling update() will print
+    the string followed by only a carriage return (instead of a carriage
+    return and a line feed). This can be used to implement progress bars and
+    other sorts of meters. Note that anything written by update() will be
+    erased by a subsequent update(), write(), or flush()."""
+
+    def __init__(self, verbose, stream):
+        """
+        Args:
+          verbose: whether update is a no-op
+          stream: output stream to write to
+        """
+        self._dirty = False
+        self._verbose = verbose
+        self._stream = stream
+        self._last_update = ""
+
+    def write(self, txt):
+        """Write text directly to the stream, overwriting and resetting the
+        meter."""
+        if self._dirty:
+            self.update("")
+            self._dirty = False
+        self._stream.write(txt)
+
+    def flush(self):
+        """Flush any buffered output."""
+        self._stream.flush()
+
+    def update(self, str):
+        """Write an update to the stream that will get overwritten by the next
+        update() or by a write().
+
+        This is used for progress updates that don't need to be preserved in
+        the log. Note that verbose disables this routine; we have this in
+        case we are logging lots of output and the update()s will get lost
+        or won't work properly (typically because verbose streams are
+        redirected to files.
+
+        TODO(dpranke): figure out if there is a way to detect if we're writing
+        to a stream that handles CRs correctly (e.g., terminals). That might
+        be a cleaner way of handling this.
+        """
+        if self._verbose:
+            return
+
+        # Print the necessary number of backspaces to erase the previous
+        # message.
+        self._stream.write("\b" * len(self._last_update))
+        self._stream.write(str)
+        num_remaining = len(self._last_update) - len(str)
+        if num_remaining > 0:
+            self._stream.write(" " * num_remaining + "\b" * num_remaining)
+        self._last_update = str
+        self._dirty = True