[test] Add object literal micro-benchmarks.

test/js-perf-test/SixSpeed.json

 {
   "name": "SixSpeed",
   "run_count": 3,
   "run_count_arm": 1,
   "run_count_arm64": 1,
   "timeout": 120,
   "units": "score",
   "total": true,
   "resources": ["base.js"],
   "tests": [
     {
+      "name": "Computed property names in object literals",
+      "path": ["SixSpeed/ObjectLiterals"],

[Yang, 2016/11/16 20:44:30]

So, uhm.. bikeshedding. I intended the file names to be hacker_case. Maybe we
can keep that convention? We could also rename the file name for "spread.js" to
"Spread.js", if you want. But then we have "run.js" in lowercase ... :)

+      "main": "run.js",
+      "resources": [
+        "run.js",
+        "ObjectLiterals.js"
+      ],
+      "results_regexp": "^%s\\(Score\\): (.+)$",
+      "tests": [
+        {"name": "ObjectLiterals-ES5"},
+        {"name": "ObjectLiterals-ES6"}
+      ]
+    },
+    {
       "name": "Spread",
       "path": ["SixSpeed/spread"],
       "main": "run.js",
       "resources": [
         "run.js",
         "spread.js"
       ],
       "results_regexp": "^%s\\(Score\\): (.+)$",
       "tests": [
         {"name": "Spread-ES5"},
         {"name": "Spread-Traceur"},
         {"name": "Spread-ES6"}
       ]
     }
   ]
 }