Histogram column type discovery query uses non-filtered query

Pass all queries to the dataview and use the no filters one for
discovering what is the column type associated to the histogram dataview.

lib/cartodb/models/dataview/factory.js

@@ -11,7 +11,7 @@ var DataviewFactory = {
         if (!this.dataviews[type]) {
             throw new Error('Invalid dataview type: "' + type + '"');
         }
-        return new this.dataviews[type](query, dataviewDefinition.options);
+        return new this.dataviews[type](query, dataviewDefinition.options, dataviewDefinition.sql);
     }
 };
 

lib/cartodb/models/dataview/histogram.js

@@ -109,12 +109,13 @@ var TYPE = 'histogram';
      }
  }
  */
-function Histogram(query, options) {
+function Histogram(query, options, queries) {
     if (!_.isString(options.column)) {
         throw new Error('Histogram expects `column` in widget options');
     }
 
     this.query = query;
+    this.queries = queries;
     this.column = options.column;
     this.bins = options.bins;
 
@@ -143,7 +144,7 @@ Histogram.prototype.sql = function(psql, override, callback) {
     var _column = this.column;
 
     var columnTypeQuery = columnTypeQueryTpl({
-        column: _column, query: this.query
+        column: _column, query: this.queries.no_filters
     });
 
     if (this._columnType === null) {