[Telemetry] Update all WPR json files to the new format.

tools/perf/page_sets/data/robohornet_pro.json

Index: tools/perf/page_sets/data/robohornet_pro.json
diff --git a/tools/perf/page_sets/data/robohornet_pro.json b/tools/perf/page_sets/data/robohornet_pro.json
index acd614eba56388fea10bdcce3f8c74eb5cc0097f..1d0bab76f77b708cc70993510a4ea1278819e360 100644
--- a/tools/perf/page_sets/data/robohornet_pro.json
+++ b/tools/perf/page_sets/data/robohornet_pro.json
@@ -1,8 +1,9 @@
 {
-    "description": "Describes the Web Page Replay archives for a page set. Don't edit by hand! Use record_wpr for updating.",
     "archives": {
-        "robohornet_pro_000.wpr" : [
-            "http://ie.microsoft.com/testdrive/performance/robohornetpro/"
-        ]
-    }
-}
+        "http://ie.microsoft.com/testdrive/performance/robohornetpro/": {
+            "DEFAULT": "robohornet_pro_000.wpr"
+        }
+    },
+    "description": "Describes the Web Page Replay archives for a story set. Don't edit by hand! Use record_wpr for updating.",
+    "platform_specific": true
+}