Add test-info for media_perftests.

tools/perf/test-info.json

 {
   "_description":"This file contains info about our performance test suites, used by the perf dashboard (http://chromeperf.appspot.com).",
   "blink_perf":{
     "description":"Runs all enabled benchmarks in third_party/WebKit/PerformanceTests/",
     "code":[
       "chrome/src/tools/perf/measurements/blink_perf.py",
       "third_party/WebKit/PerformanceTests/"
     ]
   },
   "canvasmark": {
@@ skipping 74 matching lines @@
   },
   "mach_ports":{
     "description":"This test spawns a new browser and counts the number of open Mach ports in the browser process. It navigates tabs and closes them, repeatedly measuring the number of open ports. This is used to protect against leaking Mach ports, which was the source of [bug 105513](http://crbug.com/105513).",
     "code":[
       "chrome/src/chrome/test/perf/mach_ports_test.cc"
     ]
   },
   "media.tough_video_cases":{
     "description":"Obtains media metrics for key user scenarios."
   },
+  "media_perftests":{
+    "description":"Microbenchmarks for media (media/) component.",
+    "code":[
+      "chrome/src/media/media.gyp",
+    ]
+  },
   "memory.reload.2012Q3":{
     "description":"Memory consumption for a set of top pages from 2012, reloading and garbage collecting on each page load."
   },
   "memory.top_25":{
     "description":"Use (recorded versions of) real world web sites and measure memory consumption."
   },
   "memory_test":{
     "description":"Loads a number of URLs across tabs and windows and measures the memory usage.",
     "code":[
       "chrome/src/chrome/test/perf/memory_test.cc"
@@ skipping 73 matching lines @@
     "description":"Measures warm startup time with a dirty profile.",
     "comment":"The same as startup.warm.blank_page, except for the user profile that's used. Set up in tools/build/scripts/master/factory/chromium_factory.py."
   },
   "sunspider":{
     "description":"Performance on the [SunSpider JavaScript benchmark](http://www.webkit.org/perf/sunspider/sunspider.html)"
   },
   "tab_switching.top_10":{
     "description":"This test records the MPArch.RWH_TabSwitchPaintDuration histogram, which is a measure of the time between when a tab was requested to be shown, and when first paint occurred. The script opens 10 pages in different tabs, waits for them to load, and then switches to each tab and records the metric. The pages were chosen from Alexa top ranking sites."
   }
 }