http://pastebin.com/mbhQnibu

mkLocalManifest.py

#!/usr/bin/env python

import os, sys
import subprocess
import StringIO
import xml.dom.minidom

def getTop():
    for v in ('TOP', 'ANDROID_BUILD_TOP'):
        if v in os.environ:
            return os.getenv(v)
    if os.access('.repo/manifest.xml', os.R_OK):
        return os.getcwd()

def getOutput(command):
    output = subprocess.Popen(command, stdout=subprocess.PIPE).communicate()[0]
    return StringIO.StringIO(output)

def gitSync(path):
    os.chdir(path)
    if os.system('git pull'):
        sys.exit(-1)

def getPaths(manifest):
    root = xml.dom.minidom.parse(manifest)
    path = set()

    for node in root.childNodes[0].childNodes:
        if node.nodeName != 'project':
            continue
        name = node.getAttribute('name')
        path.add(name)
    return path


def buildLocalManifest(manifestDir, repoDir):
    os.chdir(manifestDir)

    path = set()
    for line in getOutput(('git', 'branch', '-a')):
        branch = line.strip()
        if not branch.startswith('remotes/origin'):
            continue
        if branch == 'remotes/origin/master':
            continue
        manifest = getOutput(('git', 'show', '%s:default.xml'%branch))
        path.update(getPaths(manifest))

    manifest = getOutput(('git', 'show', 'default:default.xml'))
    defaultPath = getPaths(manifest)

    doc = xml.dom.minidom.Document()
    root = doc.createElement('manifest')
    doc.appendChild(root)

    for path in path - defaultPath:
        e = doc.createElement('project')
        root.appendChild(e)
        e.setAttribute('name', path)
        e.setAttribute('path', path)

    doc.writexml(open(os.path.join(repoDir, 'local_manifest.xml'), 'w'), "", "  ", "\n")


if __name__ == '__main__':
    if len(sys.argv) == 1:
        top = getTop()
    elif sys.argv[1]:
        top = sys.argv[1]
    repoDir = os.path.join(top, '.repo')
    manifestDir = os.path.join(repoDir, 'manifests')
    gitSync(manifestDir)
    buildLocalManifest(manifestDir, repoDir)