Bug 130495 Get rid of SessionHandleAdapter
Now, we use SessionHandleAdapter to keep current active report deisng. That's a bad practive for editor swith and rebuild will cuase lots of problmes. Need find way to replace it.
UI/org.eclipse.birt.report.designer.ui.editors/src/org/eclipse/birt/report/designer/ui/editors/MultiPageReportEditor.java
/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.ui.part.WorkbenchPart#getAdapter(java.lang.Class)
	 */
	public Object getAdapter( Class type )
	{
		if ( type == IReportProvider.class )
		{
			return new FileReportProvider( );
		}
		if ( type == ILibraryProvider.class )
		{
			return new LibraryProvider( );
		}
		if ( type == PalettePage.class )
		{
			Object adapter = getPalettePage( );
			updatePaletteView( getActivePageInstance( ) );
			return adapter;
		}
		if ( type == IContentOutlinePage.class )
		{