Bug 213504 [Markers] Problems View no longer supports dragging into the Editor Area
I20071218-0800. You used to be able to drag an error into the Editor Area in order to open the associated file. I commonly use the DnD gesture to open a 'problem' but it appears that this isn't working in the new version...
bundles/org.eclipse.ui.ide/src/org/eclipse/ui/internal/views/markers/ExtendedMarkersView.java
Object[] newChildren = new Object[newLength];
					System.arraycopy(children, 0, newChildren, 0, newLength);
					return newChildren;
				}
				return children;
			}
			/*
			 * (non-Javadoc)
			 * 
			 * @see org.eclipse.jface.viewers.ILazyTreeContentProvider#getParent(java.lang.Object)
			 */
			public Object getParent(Object element) {
				Object parent = ((MarkerSupportItem) element).getParent();
				if (parent == null)
					return builder;
				return parent;
			}
			/*
			 * (non-Javadoc)
			 * 
			 * @see org.eclipse.jface.viewers.ITreeContentProvider#hasChildren(java.lang.Object)
			 */
			public boolean hasChildren(Object element) {
				return ((MarkerSupportItem) element).getChildren().length > 0;
			}
			/*
			 * (non-Javadoc)
			 * 
			 * @see org.eclipse.jface.viewers.IContentProvider#inputChanged(org.eclipse.jface.viewers.Viewer,
			 *      java.lang.Object, java.lang.Object)