Bug 139110 GUI enhancement to support create subquery more conveniently.
Description: GUI enhancement to support create subquery more conveniently. Steps to reproduce: Subquery means insert table/list inside another table/list item, and the inner table/list item doesn't has its own dataset binding. In latest build, if you want to creat a subquery structure, you have to use dataSetRow as binding expression for data items in inner table/list item. For example: 1. Insert a list, generate column data binding for it. 2. Add a group for the list. 3. Insert table to list group header which is used to display data rows in list group. Dont' bind table to dataset. 4. Insert a data to table detail row. 5. New a binding column for data, click to Open Expression Builder. The issue is that only "Availabel column bindings" is listed in Category but no "Available Data Sets". So I have to type dataSetRow[".."] by myself to generate correct subquery. For users, maybe they will mistakenly use "Available column bindings" which will generate expression like row._outer[".."] and get wrong result. So it is recommended to add "Available Data Sets" in Expression Builder for such case.
UI/org.eclipse.birt.report.designer.core/src/org/eclipse/birt/report/designer/util/DEUtil.java
import org.eclipse.birt.report.model.api.ComputedColumnHandle;
import org.eclipse.birt.report.model.api.DataItemHandle;
import org.eclipse.birt.report.model.api.DataSetHandle;
import org.eclipse.birt.report.model.api.DataSourceHandle;
import org.eclipse.birt.report.model.api.DesignElementHandle;
import org.eclipse.birt.report.model.api.DesignEngine;
import org.eclipse.birt.report.model.api.DimensionHandle;
import org.eclipse.birt.report.model.api.GraphicMasterPageHandle;
import org.eclipse.birt.report.model.api.GridHandle;
import org.eclipse.birt.report.model.api.GroupElementFactory;
import org.eclipse.birt.report.model.api.GroupElementHandle;
import org.eclipse.birt.report.model.api.GroupHandle;
import org.eclipse.birt.report.model.api.ImageHandle;
import org.eclipse.birt.report.model.api.LabelHandle;
import org.eclipse.birt.report.model.api.LibraryHandle;
import org.eclipse.birt.report.model.api.ListingHandle;
import org.eclipse.birt.report.model.api.MasterPageHandle;
import org.eclipse.birt.report.model.api.ModuleHandle;
import org.eclipse.birt.report.model.api.ParameterGroupHandle;
import org.eclipse.birt.report.model.api.ParameterHandle;
import org.eclipse.birt.report.model.api.ReportDesignHandle;
import org.eclipse.birt.report.model.api.ReportElementHandle;
import org.eclipse.birt.report.model.api.ReportItemHandle;
import org.eclipse.birt.report.model.api.ResultSetColumnHandle;
import org.eclipse.birt.report.model.api.RowHandle;
import org.eclipse.birt.report.model.api.SlotHandle;
import org.eclipse.birt.report.model.api.StyleHandle;
import org.eclipse.birt.report.model.api.TableHandle;
import org.eclipse.birt.report.model.api.TextItemHandle;
import org.eclipse.birt.report.model.api.ThemeHandle;