[tools] Initialize global pages var in callstats.html

tools/callstats.html

Index: tools/callstats.html
diff --git a/tools/callstats.html b/tools/callstats.html
index 2140706c3a7933bcf535dbcd7074048fcb00b360..cb2e0bea3e31adf49f15941f826cf30657c83c02 100644
--- a/tools/callstats.html
+++ b/tools/callstats.html
@@ -1043,11 +1043,11 @@ code is governed by a BSD-style license that can be found in the LICENSE file.
     }
 
     function handleLoadText(text) {
-      pages = new Pages();
       handleLoadJSON(JSON.parse(text));
     }
 
     function handleLoadJSON(json) {
+      pages = new Pages();
       versions = Versions.fromJSON(json);
       initialize()
       showPage(versions.versions[0].pages[0]);