Bug 90528 Editor icon does not show problem decoration for second instance
3.1 M6 - open a .java file that has errors or warnings - the editor tab icon has the problem decoration - Window > New Window - open the same file in the new window - the editor tab icon is missing the problem decoration
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/javaeditor/CompilationUnitEditor.java
continue;
					int offset= position.getOffset();
					int length= position.getLength();
					int end= offset + length;
					if (offset >= eventOffset + eventOldLength) 
						
						
						position.setOffset(offset + deltaLength);
					else if (end <= eventOffset) {
						
						
					} else if (offset <= eventOffset && end >= eventOffset + eventOldLength) {
						
						position.setLength(length + deltaLength);
					} else if (offset < eventOffset) {
						
						int newEnd= eventOffset;
						position.setLength(newEnd - offset);
					} else if (end > eventOffset + eventOldLength) {
						
						
						
						int newOffset= eventOffset + eventNewLength;
						position.setOffset(newOffset);
						position.setLength(end - newOffset);
					} else {
						
						position.delete();
					}
				}