Don't rely on CpuStats.Percent

Just do the math client-side with TotalTicks and Reserved

ui/app/models/allocation.js

@@ -57,8 +57,13 @@ export default Model.extend({
     return used / total;
   }),
 
-  percentCPU: computed('stats.ResourceUsage.CpuStats.Percent', function() {
-    return this.get('stats.ResourceUsage.CpuStats.Percent') || 0;
+  percentCPU: computed('cpuUsed', 'taskGroup.reservedCPU', function() {
+    const used = this.get('cpuUsed');
+    const total = this.get('taskGroup.reservedCPU');
+    if (!total || !used) {
+      return 0;
+    }
+    return used / total;
   }),
 
   stats: computed('node.{isPartial,httpAddr}', function() {

ui/tests/acceptance/client-detail-test.js

@@ -172,7 +172,7 @@ test('each allocation should have high-level details for the allocation', functi
         .find('td:eq(6)')
         .text()
         .trim(),
-      allocStats.resourceUsage.CpuStats.Percent,
+      Math.floor(allocStats.resourceUsage.CpuStats.TotalTicks) / cpuUsed,
       'CPU %'
     );
     assert.equal(

ui/tests/acceptance/task-group-detail-test.js

@@ -217,7 +217,7 @@ test('each allocation should show stats about the allocation, retrieved directly
       .find('td:eq(6)')
       .text()
       .trim(),
-    allocStats.resourceUsage.CpuStats.Percent,
+    Math.floor(allocStats.resourceUsage.CpuStats.TotalTicks) / cpuUsed,
     'CPU %'
   );