Bug 76887 [content assist] Template validation is case sensitive
Test case: Type SYS Ctrl-Space Type o You are left with no code completions. This differs from the code completion proposals where the prefix matching is not case sensitive. (note this is a problem in both the JDT TemplateProposal and the JFace text TemplateProposal)
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/text/template/contentassist/TemplateProposal.java
LinkedModeModel model= new LinkedModeModel();
			TemplateVariable[] variables= templateBuffer.getVariables();
			
			MultiVariableGuess guess= fContext instanceof CompilationUnitContext ? ((CompilationUnitContext) fContext).getMultiVariableGuess() : null;
		
			boolean hasPositions= false;
			for (int i= 0; i != variables.length; i++) {
				TemplateVariable variable= variables[i];
				if (variable.isUnambiguous())
					continue;
				
				LinkedPositionGroup group= new LinkedPositionGroup();
				
				int[] offsets= variable.getOffsets();
				int length= variable.getLength();
				
				LinkedPosition first;
				if (guess != null && variable instanceof MultiVariable) {
					first= new VariablePosition(document, offsets[0] + start, length, guess, (MultiVariable) variable);
					guess.addSlave((VariablePosition) first);
				} else {
					String[] values= variable.getValues();
					ICompletionProposal[] proposals= new ICompletionProposal[values.length];
					for (int j= 0; j < values.length; j++) {
						ensurePositionCategoryInstalled(document, model);
						Position pos= new Position(offsets[0] + start, length);
						document.addPosition(getCategory(), pos);
						proposals[j]= new PositionBasedCompletionProposal(values[j], pos, length);
					}