Browser Action Toggle https://plus.google.com/u/0/114182909067816580108/posts/gqTjknY4Bs6

background.js

chrome.browserAction.setPopup({
  popup: "popup.html"
})


chrome.browserAction.onClicked.addListener(function() {
	chrome.browserAction.setPopup({
		popup: "popup.html"
	})
});

chrome.extension.onConnect.addListener(function(port) {
	if(port.name == "popuptoggle") {

		chrome.browserAction.setPopup({
			popup: ""
		});

		port.onDisconnect.addListener(function(a) {
			setTimeout(function() {
				chrome.browserAction.setPopup({
					popup: "popup.html"
				})
			}, 100);
		});

	}
});

popup.js

var port = chrome.extension.connect({name: "popuptoggle"});