Introduce new target type called "_browser", in order to specify browser default link handling

- Description widget using href, the default target would be _browser
- Call filemanager egw.open with target _browser

etemplate/js/et2_widget_description.js

@@ -70,7 +70,7 @@ var et2_description = expose(et2_baseWidget.extend([et2_IDetachedDOM],
 		"extra_link_target": {
 			"name": "Link target",
 			"type": "string",
-			"default": "_self",
+			"default": "_browser",
 			"description": "Link target for href attribute"
 		},
 		"extra_link_popup": {

filemanager/js/app.js

@@ -745,7 +745,7 @@ app.classes.filemanager = AppJS.extend(
 		}
 		else
 		{
-			egw.open({path: path, type: data.data.mime}, 'file');
+			egw.open({path: path, type: data.data.mime}, 'file','view',null,'_browser');
 		}
 		return false;
 	},

phpgwapi/js/jsapi/egw_open.js

@@ -334,27 +334,18 @@ egw.extend('open', egw.MODULE_WND_LOCAL, function(_egw, _wnd)
 			}
 			else if ((typeof _target == 'undefined' || _target == '_self' || typeof this.link_app_list()[_target] != "undefined"))
 			{
-				// No mime type registered, set target properly based on browsing environment
-				if (!mime_info)
-				{
-					_target = egwIsMobile()?'_self':'_blank';
-				}
 				if(_target == '_self')
 				{
 					// '_self' isn't allowed, but we can handle it
 					_target = undefined;
 				}
-				else
-				{
-					return _wnd.open(url, _target);
-				}
 				// Use framework's link handler, if present
 				return this.link_handler(url,_target);
 			}
 			else
 			{
 				// No mime type registered, set target properly based on browsing environment
-				if (!mime_info)
+				if (_target == '_browser')
 				{
 					_target = egwIsMobile()?'_self':'_blank';
 				}