Map / Avoid JSON parse error on context having layer with filter. Clear

queue on context load.

Context layer can contain a JSON extension which could be formatted and
XML formatting may add extra space which needs to be clean up for proper
JSON string:

```xml
       <ows-context:Layer name="surval_parametre_point" group="/Human Activities" hidden="false" opacity="1"
                           showLayerInfo="true">
            <ows:Title>Surval données par paramètre (point)</ows:Title>
            <ows-context:Server service="urn:ogc:serviceType:WMS" version="1.3.0">
                <ows-context:OnlineResource xlink:href="https://sextant.ifremer.fr/services/wms/environnement_marin"/>
            </ows-context:Server>
            <ows-context:Extension>{"uuid":"cf5048f6-5bbf-4e44-ba74-e6f429af51ea","label":"Surval données par paramètre
                (point)","filters":{"qParams":{"ft_LIEU_LIBELLE_s":{"type":"terms","values":{"001-P-003 - Zuydcoote
                filière":true}}}},"wfsUrl":"https://sextant.ifremer.fr/services/wfs/environnement_marin"}
            </ows-context:Extension>
        </ows-context:Layer>
```

Clear map queue on load - may have side effect when loading differents
maps quickly.

Avoid JS error if server layer is not defined (which should not be the
case unless custom context with new layer types was created).

web-ui/src/main/resources/catalog/components/common/map/wmsQueue.js

@@ -45,6 +45,14 @@
       this.queue = queue;
       this.errors = errors;
 
+      var clear = function (map) {
+        var type = (map && map.get && map.get("type")) || "viewer";
+        if (queue[type]) {
+          queue[type].queue.length = 0;
+          queue[type].errors.length = 0;
+        }
+      };
+
       var getMapType = function (map) {
         var type = (map && map.get && map.get("type")) || "viewer";
         if (queue[type] === undefined) {

web-ui/src/main/resources/catalog/components/viewer/baselayerswitcher/BaseLayerSwitcherDirective.js

@@ -38,13 +38,15 @@
     "gnViewerSettings",
     "gnSearchSettings",
     "gnOwsContextService",
+    "gnWmsQueue",
     "$rootScope",
     "gnMapsManager",
     "gnMap",
     function (
       gnViewerSettings,
       gnSearchSettings,
       gnOwsContextService,
+      gnWmsQueue,
       $rootScope,
       gnMapsManager,
       gnMap
@@ -91,6 +93,7 @@
 
           scope.reset = function () {
             $rootScope.$broadcast("owsContextReseted");
+            gnWmsQueue.clear(scope.map);
             var mapViewerConfig = gnMap.getMapConfig()["map-" + gnMapsManager.VIEWER_MAP];
             if (gnViewerSettings.defaultContext) {
               loadContext();

web-ui/src/main/resources/catalog/components/viewer/owscontext/OwsContextService.js

@@ -311,7 +311,8 @@
               // load extension content (JSON)
               var extension =
                 layer.extension && layer.extension.any
-                  ? JSON.parse(layer.extension.any)
+                  ? // Formatted XML may contains extra space and line feed
+                    JSON.parse(layer.extension.any.replaceAll("\\n^ +", " "))
                   : {};
 
               var loadingId = extension.label ? extension.label : layer.name;
@@ -710,8 +711,11 @@
        * @param {numeric} index of the layer in the tree
        */
       this.createLayer = function (layer, map, bgIdx, index, style) {
-        var server = layer.server[0];
-        var res = server.onlineResource[0];
+        var res = { href: "" };
+        if (layer.server) {
+          var server = layer.server[0];
+          res = server.onlineResource[0];
+        }
         var createOnly = angular.isDefined(bgIdx) || angular.isDefined(index);
 
         if (layer.name && layer.name.match(reT)) {