Bug 180842 Config memory buffer size in data engine execution.
To tuning the performance, it is necessary for DtE to expose API for clients to config the size of memory it used to store the final result set. A new AppContext string, "org.eclipse.birt.data.cache.memory.size" is proposed. The new appcontext entry only accept positive integer as input, the unit of which would be MB.
data/org.eclipse.birt.data/src/org/eclipse/birt/data/engine/impl/document/viewing/DummyEventHandler.java
* (non-Javadoc)
	 * @see org.eclipse.birt.data.engine.odi.IEventHandler#getExecutorHelper()
	 */
	public IExecutorHelper getExecutorHelper( )
	{
		return null;
	}
	/*
	 * (non-Javadoc)
	 * @see org.eclipse.birt.data.engine.odi.IEventHandler#setExecutorHelper(org.eclipse.birt.data.engine.impl.ExecutorHelper)
	 */
	public void setExecutorHelper( IExecutorHelper helper )
	{
				
	}
	/*
	 * (non-Javadoc)
	 * @see org.eclipse.birt.data.engine.odi.IEventHandler#getExprs()
	 */
	public Map getColumnBindings( )
	{
		return null;
	}
	public Map getAllColumnBindings() {
		
		return null;
	}
	
}