fix get union for sparklines

cell/model/WorkbookElems.js

@@ -5315,10 +5315,11 @@ CellArea.prototype = {
 			if (0 === i) {
 				result.assign2(item.sqref);
 			} else {
-				result.union(item.sqref);
+				result.addRange();
+				result.getLast().assign2(item.sqref);
 			}
 		});
-		return result;
+		return result.getUnion();
 	};
 	sparklineGroup.prototype.asc_getId = function () {
 		return this.Id;

cell/utils/utils.js

@@ -701,6 +701,28 @@
 				this.getLast().assign2(range);
 			}
 		};
+		SelectionRange.prototype.getUnion = function () {
+			var result = new SelectionRange();
+			var unionRanges = function (ranges, res) {
+				ranges.forEach(function (item, i) {
+					if (0 === i) {
+						res.assign2(item);
+					} else {
+						res.union(item);
+					}
+				});
+			};
+			unionRanges(this.ranges, result);
+
+			var isUnion = true, resultTmp;
+			while (isUnion && !result.isSingleRange()) {
+				resultTmp = new SelectionRange();
+				unionRanges(result.ranges, resultTmp);
+				isUnion = result.ranges.length !== resultTmp.ranges.length;
+				result = resultTmp;
+			}
+			return result;
+		};
 		SelectionRange.prototype.offsetCell = function (dr, dc, fCheckSize) {
 			var done, curRange, mc;
 			var lastRow = this.activeCell.row;