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// Log JS errors with Google Analytics
// https://developer.mozilla.org/en-US/docs/Web/API/GlobalEventHandlers.onerror
// https://developers.google.com/analytics/devguides/collection/gajs/methods/gaJSApiEventTracking#_gat.GA_EventTracker_._trackEvent
(function() {
	
	var saveTheOldOnError = window.onerror;
	
	// Override previous handler.
	window.onerror = function myErrorHandler(errorMsg, url, lineNumber) {
		
		if (saveTheOldOnError) {
			// Call previous handler.
			return saveTheOldOnError(errorMsg, url, lineNumber);
		}
		
		
		(function(errorMsg, url, lineNumber) {
			setTimeout(function() {
//console.log(errorMsg + ', line number ' + lineNumber + ', on page ' + window.location.href);
				window._gaq = window._gaq || [];
				window._gaq.push(
					[
						'_trackEvent'
						,'JSErrorDetect' // Category, string
						,errorMsg + ', ' + lineNumber + ', ' + url // Action, string
						,window.location.href // Label, string
						,1 // Value
						,true // Non-interaction, boolean
					]
				);
			},100);
		}(errorMsg, url, lineNumber));
		
		// Just let default handler run.
		return false;
		
	};
	
}());