Bug 40772 [plan item] Smart tab on empty lines
When having the caret on an empty line, pressing tab cleans up the line and sets the caret it the right indentation column.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/text/java/JavaAutoIndentStrategy.java
if (openingParen > pos)
				continue;
			if (looksLikeAnonymousClassDef(document, openingParen - 1, partitioning))
				return closingParen + 1;
		}
		return -1;
	}
	/**
	 * Finds a closing parenthesis to the left of <code>position</code> in document, where that parenthesis is only
	 * separated by whitespace from <code>position</code>. If no such parenthesis can be found, <code>position</code> is returned.
	 * 
	 * @param document the document being modified
	 * @param position the first character position in <code>document</code> to be considered
	 * @param partitioning the document partitioning
	 * @return the position of a closing parenthesis left to <code>position</code> separated only by whitespace, or <code>position</code> if no parenthesis can be found
	 */
	private static int findClosingParenToLeft(IDocument document, int position, String partitioning) {
		final char CLOSING_PAREN= ')';
		try {
			if (position < 1)
				return position;
			int nonWS= firstNonWhitespaceBackward(document, position - 1, partitioning, -1);
			if (nonWS != -1 && document.getChar(nonWS) == CLOSING_PAREN)
				return nonWS;
		} catch (BadLocationException e1) {
		}
		return position;
	}
	/**