main, frozen columns

public/web/sheet/sheet_data_helper.js

@@ -41,6 +41,9 @@ var SheetDataHelper = {
         return spread;
     },
     loadSheetHeader: function (setting, sheet) {
+        if (setting.frozenCols) {
+            sheet.frozenColumnCount(setting.frozenCols);
+        }
         sheet.setColumnCount(setting.cols.length);
         sheet.setRowCount(setting.headRows, GC.Spread.Sheets.SheetArea.colHeader);
         setting.headRowHeight.forEach(function (rowHeight, index) {

public/web/tree_sheet/tree_sheet_helper.js

@@ -27,6 +27,9 @@ var TREE_SHEET_HELPER = {
         return style;
     },
     loadSheetHeader: function (setting, sheet) {
+        if (setting.frozenCols) {
+            sheet.frozenColumnCount(setting.frozenCols);
+        }
         sheet.setColumnCount(setting.cols.length);
         sheet.setRowCount(setting.headRows, GC.Spread.Sheets.SheetArea.colHeader);
         setting.headRowHeight.forEach(function (rowHeight, index) {

test/tmp_data/bills_grid_setting.js

@@ -4,6 +4,7 @@
 var BillsGridSetting ={
     "emptyRows":3,
     "headRows":1,
+    "frozenCols": 4,
     "treeCol": 0,
     "headRowHeight":[
         47