clearing chrome dns cache and sockets via js

flush_chrome_dns.sh

#!/bin/bash
#
# The MIT License (MIT)

# Copyright (c) 2015 Justin Shattuck <[email protected]>, F5 Networks, Inc.

# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
# in the Software without restriction, including without limitation the rights
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
# copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:

# The above copyright notice and this permission notice shall be included in
# all copies or substantial portions of the Software.

# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
# THE SOFTWARE.

echo ""
echo "Dumping Google Chrome DNS Cache"
osascript <<EOD
	tell application "Google Chrome"
		tell front window
			set origTab to active tab
			set origTabIndex to active tab index
			set theTab to make new tab with properties {URL:"chrome://net-internals/#dns"}
			set isLoadDone to not loading of theTab
			repeat until isLoadDone
				set isLoadDone to not loading of theTab
			end repeat
			delay 1
			execute theTab javascript "g_browser.sendFlushSocketPools();g_browser.checkForUpdatedInfo(false);g_browser.sendClearHostResolverCache();"
			close theTab
			set active tab index to origTabIndex
			-- uncomment the line below (remove -- ) if you would like previously opened tab to be reloaded.
			-- reload origTab
		end tell
	end tell
EOD

echo "Finished dumping Google Chrome DNS Cache"

when i use this i got
Uncaught ReferenceError: g_browser is not defined at <anonymous>:1:17