Revert r80770 "Switch from xml.dom.minidom to xml.etree"

Throws exceptions on mac.

R=dpranke@chromium.org
BUG=
TEST=

Review URL: http://codereview.chromium.org/6811020

git-svn-id: svn://svn.chromium.org/chrome/trunk/tools/depot_tools@80771 0039d316-1c4b-4281-b951-d872f2087c98

gclient_utils.py

@@ -14,6 +14,8 @@ import subprocess
 import sys
 import threading
 import time
+import xml.dom.minidom
+import xml.parsers.expat
 
 
 def hack_subprocess():
@@ -112,6 +114,29 @@ def SplitUrlRevision(url):
   return tuple(components)
 
 
+def ParseXML(output):
+  try:
+    return xml.dom.minidom.parseString(output)
+  except xml.parsers.expat.ExpatError:
+    return None
+
+
+def GetNamedNodeText(node, node_name):
+  child_nodes = node.getElementsByTagName(node_name)
+  if not child_nodes:
+    return None
+  assert len(child_nodes) == 1 and child_nodes[0].childNodes.length == 1
+  return child_nodes[0].firstChild.nodeValue
+
+
+def GetNodeNamedAttributeText(node, node_name, attribute_name):
+  child_nodes = node.getElementsByTagName(node_name)
+  if not child_nodes:
+    return None
+  assert len(child_nodes) == 1
+  return child_nodes[0].getAttribute(attribute_name)
+
+
 def SyntaxErrorToError(filename, e):
   """Raises a gclient_utils.Error exception with the human readable message"""
   try: