Optimization: prevent double ticks array reverse for vertical logarit…

…hmic axis (chartjs#5076)

with ticks option 'reverse: true'.

src/scales/scale.logarithmic.js

@@ -161,32 +161,30 @@ module.exports = function(Chart) {
 			var me = this;
 			var opts = me.options;
 			var tickOpts = opts.ticks;
+			var reverse = !me.isHorizontal();
 
 			var generationOptions = {
 				min: tickOpts.min,
 				max: tickOpts.max
 			};
 			var ticks = me.ticks = Ticks.generators.logarithmic(generationOptions, me);
 
-			if (!me.isHorizontal()) {
-				// We are in a vertical orientation. The top value is the highest. So reverse the array
-				ticks.reverse();
-			}
-
 			// At this point, we need to update our max and min given the tick values since we have expanded the
 			// range of the scale
 			me.max = helpers.max(ticks);
 			me.min = helpers.min(ticks);
 
 			if (tickOpts.reverse) {
-				ticks.reverse();
-
+				reverse = !reverse;
 				me.start = me.max;
 				me.end = me.min;
 			} else {
 				me.start = me.min;
 				me.end = me.max;
 			}
+			if (reverse) {
+				ticks.reverse();
+			}
 		},
 		convertTicksToLabels: function() {
 			this.tickValues = this.ticks.slice();