WebRTC: Add/rename peerconnection_unittests test

scripts/slave/recipes/webrtc/standalone.expected/tryserver_webrtc_android_rel.json

 [
   {
     "cmd": [
       "python",
       "-u",
       "[BUILD]/scripts/slave/bot_update.py",
       "--master",
       "tryserver.webrtc",
       "--builder",
       "android_rel",
@@ skipping 415 matching lines @@
     },
     "name": "modules_unittests"
   },
   {
     "cmd": [
       "python",
       "-u",
       "[SLAVE_BUILD]/src/webrtc/build/android/test_runner.py",
       "gtest",
       "-s",
+      "peerconnection_unittests",
+      "--blacklist-file",
+      "[SLAVE_BUILD]/src/out/bad_devices.json",
+      "--verbose",
+      "--release",
+      "--isolate_file_path=[SLAVE_BUILD]/src/talk/peerconnection_unittests.isolate",
+      "-t",
+      "900"
+    ],
+    "cwd": "[SLAVE_BUILD]",
+    "env": {
+      "PATH": "[SLAVE_BUILD]/src/third_party/android_tools/sdk/platform-tools:[SLAVE_BUILD]/src/build/android:%(PATH)s"
+    },
+    "name": "peerconnection_unittests"
+  },
+  {
+    "cmd": [
+      "python",
+      "-u",
+      "[SLAVE_BUILD]/src/webrtc/build/android/test_runner.py",
+      "gtest",
+      "-s",
       "system_wrappers_unittests",
       "--blacklist-file",
       "[SLAVE_BUILD]/src/out/bad_devices.json",
       "--verbose",
       "--release",
       "--isolate_file_path=[SLAVE_BUILD]/src/webrtc/system_wrappers/system_wrappers_unittests.isolate",
       "-t",
       "900"
     ],
     "cwd": "[SLAVE_BUILD]",
@@ skipping 255 matching lines @@
       "@@@STEP_LOG_LINE@python.inline@  os.remove(report)@@@",
       "@@@STEP_LOG_END@python.inline@@@"
     ]
   },
   {
     "name": "$result",
     "recipe_result": null,
     "status_code": 0
   }
 ]