metrics: Convert timestamp and depot_tools_age to integers.

TBR=ajp@chromium.org

Change-Id: I839997c132ad7b9642e795b9562bf4fea18211f4
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/1585271
Commit-Queue: Edward Lesmes <ehmaldonado@chromium.org>
Reviewed-by: Edward Lesmes <ehmaldonado@chromium.org>

metrics.py

@@ -214,14 +214,14 @@ class MetricsCollector(object):
     self.add('exit_code', exit_code)
 
     # Add metrics regarding environment information.
-    self.add('timestamp', time.time())
+    self.add('timestamp', int(time.time()))
     self.add('python_version', metrics_utils.get_python_version())
     self.add('host_os', gclient_utils.GetMacWinOrLinux())
     self.add('host_arch', detect_host_arch.HostArch())
 
     depot_tools_age = metrics_utils.get_repo_timestamp(DEPOT_TOOLS)
     if depot_tools_age is not None:
-      self.add('depot_tools_age', depot_tools_age)
+      self.add('depot_tools_age', int(depot_tools_age))
 
     git_version = metrics_utils.get_git_version()
     if git_version: