Edit in JSFiddle

var myApp = angular.module('myApp', []);

function HomeCtrl($scope) {
    $scope.lines = [];
    $scope.addLine = function(lineText) {
        //$scope.chat.addLine($scope.lineText);
        $scope.lines.push({
            text: $scope.lineText
        });
        $scope.lineText = ''
    };
}

<script type="text/ng-template" id="/tpl1.html">
  <form ng-submit="addLine()">
    <input type="text" ng-model="$parent.lineText" size="30" placeholder="Type your message here">
  </form>
</script>

<div ng-controller="HomeCtrl">
   <div ng-include src="'/tpl1.html'"></div>
    {{lines}}
</div>