IWYU: std::numeric_limits is defined in limits

Change-Id: Ifbc379adc5bb7242c21e7da0bcfc28f49e4dd06f
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2153111Reviewed-by: François Doray <fdoray@chromium.org>
Commit-Queue: François Doray <fdoray@chromium.org>
Cr-Commit-Position: refs/heads/master@{#760075}

chrome/browser/performance_manager/graph/policies/background_tab_loading_policy_helpers.cc

@@ -5,6 +5,7 @@
 #include "chrome/browser/performance_manager/graph/policies/background_tab_loading_policy_helpers.h"
 
 #include <math.h>
+#include <limits>
 
 #include "base/logging.h"