Bug 179898 Date/Time type X-Axis labels are not correct when set grouping [0001]
Description: Date/Time type X-Axis labels are not correct when set grouping. Build number: 2.2.0.v20070328-0630 Steps to reproduce: 1. New a Bar Chart with Date/Time type X-Axis with values as 4/1/2005 10:12 AM 4/1/2005 11:15 AM 4/1/2005 7:15 AM 2. Enable X Series Grouping, set Type as "DateTime", Unit as "Day", Interval as 1, and Aggregate Expression as "Sum". 3. Preview. Expected result: X-Axis label should be "4/1/2005" Actual result: X-Axis label is "2005" Error log: N/A
chart/org.eclipse.birt.chart.engine/src/org/eclipse/birt/chart/util/CDateTime.java
else if ( iUnit == Calendar.MONTH )
		{
			return MILLIS_IN_DAY * 30.4375;
		}
		else if ( iUnit == Calendar.YEAR )
		{
			return MILLIS_IN_DAY * 365.25;
		}
		return 0;
	}
	/**
	 * Zeroes out all units for this datetime instance below a specified unit.
	 * 
	 * @param iUnit
	 *            The unit below which all values are to be zeroed out
	 */
	public final void clearBelow( int iUnit )
	{
		if ( iUnit == YEAR )
		{
			set( Calendar.MILLISECOND, 0 );
			set( Calendar.SECOND, 0 );
			set( Calendar.MINUTE, 0 );
			set( Calendar.HOUR, 0 );
			set( Calendar.DATE, 1 );
			set( Calendar.AM_PM, AM );
			set( Calendar.MONTH, 0 );
		}
		else if ( iUnit == MONTH )
		{