Bug 89971 [Viewers] Viewers that use IViewerLabelProvider do too many instanceof checks
M6 Checking our viewer the calls to buildLabel are doing too many instanceof checks. As a result certain viewers (such as the table viewer) are twice as slow as they were in 3.0 due to these checks. I have written some performance suites to test the Table, Tree, List and Combo viewers. Table and Tree have this issue.
bundles/org.eclipse.jface/src/org/eclipse/jface/viewers/TableViewer.java
* the ITableColorProvider.
	 * @see ITableColorProvider
	 * @see ITableFontProvider
	 */
	
	private class TableColorAndFontCollector{
		
		ITableFontProvider fontProvider = null;
		ITableColorProvider colorProvider = null;
		
		/**
		 * Create an instance of the receiver. Set the color and font
		 * providers if provider can be cast to the correct type.
		 * @param provider IBaseLabelProvider
		 */
		public TableColorAndFontCollector(IBaseLabelProvider provider){
			if(provider instanceof ITableFontProvider)
				fontProvider = (ITableFontProvider) provider;
			if(provider instanceof ITableColorProvider)
				colorProvider = (ITableColorProvider) provider;
		}
		
		/**
		 * Create an instance of the receiver with no color and font
		 * providers.
		 */
		public TableColorAndFontCollector(){
		}
		
		/**