Bug 43035 Smart Tab ends up at offset 0
Have a line that has an indent greater than it is required. Place cursor at the correct indent position. Press Tab. => Cursor ends up at the beginning of the document.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/actions/IndentAction.java
JavaPlugin.log(new Status(IStatus.ERROR, JavaPlugin.getPluginId(), IStatus.OK, null, e));
						
					} finally {
						
						if (target != null) {
							target.endCompoundChange();
							target.setRedraw(true);
						}
					}
				}
			};
			
			if (nLines > 50) {
				Display display= getTextEditor().getEditorSite().getWorkbenchWindow().getShell().getDisplay();
				BusyIndicator.showWhile(display, runnable);
			} else
				runnable.run();
			
		}
	}
	
	/**
	 * Indents a single line using the java heuristic scanner. Javadoc and multiline comments are 
	 * indented as specified by the <code>JavaDocAutoIndentStrategy</code>.
	 * 
	 * @param document the document
	 * @param line the line to be indented
	 * @param indenter the java indenter
	 * @param scanner the heuristic scanner
	 * @return the position in document after the indentation