GT-3323 - GTree - fix bug in restoring tree state after a filter where

the user did not click the tree

Ghidra/Framework/Docking/src/main/java/docking/widgets/tree/GTree.java

@@ -310,15 +310,31 @@ public class GTree extends JPanel implements BusyListener {
 		}
 	}
 
-// TODO: doc on how to override to extend listener stuff
 	protected JTreeMouseListenerDelegate createMouseListenerDelegate() {
 		return new GTreeMouseListenerDelegate(tree, this);
 	}
 
+	/**
+	 * Returns the tree state that should be used when clearing a tree filter.  This state
+	 * is tracked by the tree.  It allows the tree to remember the users tree selection
+	 * before, during and after filter operations.
+	 * 
+	 * @return the state
+	 */
 	public GTreeState getRestoreTreeState() {
 		return restoreTreeState;
 	}
 
+	/**
+	 * This allows the filter task to tell the this tree when to save its initial state
+	 * @see #getRestoreTreeState()
+	 */
+	void initializeRestoreTreeState() {
+		if (restoreTreeState == null) {
+			restoreTreeState = new GTreeState(this);
+		}
+	}
+
 	/**
 	 * Returns a state object that allows this tree to later restore its expanded and selected
 	 * state.

Ghidra/Framework/Docking/src/main/java/docking/widgets/tree/GTreeFilterTask.java

@@ -31,8 +31,22 @@ public class GTreeFilterTask extends GTreeTask {
 		super(tree);
 		this.filter = filter;
 
-		// save this now, before we modify the tree
-		defaultRestoreState = tree.getTreeState();
+		defaultRestoreState = getDefaultRestoreState();
+	}
+
+	private GTreeState getDefaultRestoreState() {
+
+		GTreeState state = tree.getRestoreTreeState();
+		if (filter == null) {
+			// clearing the filter; no need to initialize the restore state
+			return state;
+		}
+
+		if (state == null) {
+			tree.initializeRestoreTreeState();
+			state = tree.getRestoreTreeState();
+		}
+		return state;
 	}
 
 	@Override
@@ -81,8 +95,9 @@ public class GTreeFilterTask extends GTreeTask {
 
 	private void restoreInSameTask(TaskMonitor monitor) {
 
-		GTreeState existingState = tree.getRestoreTreeState();
-		GTreeState state = (existingState == null) ? defaultRestoreState : existingState;
+		GTreeState treesPreferredState = tree.getRestoreTreeState();
+		GTreeState state =
+			(treesPreferredState == null) ? defaultRestoreState : treesPreferredState;
 		GTreeRestoreTreeStateTask restoreTask = new GTreeRestoreTreeStateTask(tree, state);
 		restoreTask.run(monitor);
 	}

Ghidra/Framework/Docking/src/main/java/docking/widgets/tree/tasks/GTreeExpandPathsTask.java

@@ -17,7 +17,6 @@ package docking.widgets.tree.tasks;
 
 import java.util.List;
 
-import javax.swing.JTree;
 import javax.swing.tree.TreePath;
 
 import docking.widgets.tree.*;