Small change to datasourceSrv, if datasource is not found, return default datasource

src/app/services/datasourceSrv.js

@@ -80,7 +80,7 @@ function (angular, _, config) {
       if (!name) { return this.default; }
       if (datasources[name]) { return datasources[name]; }
 
-      throw "Unable to find datasource: " + name;
+      return this.default;
     };
 
     this.getAnnotationSources = function() {

src/css/less/variables.dark.less

@@ -35,7 +35,7 @@
 
 // Graphite Target Editor
 @grafanaTargetBorder:         @black;
-@grafana-info-box grafanaTargetBackground:     @grayDark;
+@grafanaTargetBackground:     @grayDark;
 @grafanaTargetColor:          #c8c8c8;
 @grafanaTargetColorHide:      darken(#c8c8c8, 25%);
 @grafanaTargetSegmentBorder:  #050505;