Switch to standard integer types in net/.

BUG=488550
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Review URL: https://codereview.chromium.org/1535363003 .

Cr-Commit-Position: refs/heads/master@{#366297}
diff --git a/net/base/network_quality_estimator.h b/net/base/network_quality_estimator.h
index ea4eaa1d..ad10d324 100644
--- a/net/base/network_quality_estimator.h
+++ b/net/base/network_quality_estimator.h
@@ -5,6 +5,7 @@
 #ifndef NET_BASE_NETWORK_QUALITY_ESTIMATOR_H_
 #define NET_BASE_NETWORK_QUALITY_ESTIMATOR_H_
 
+#include <stddef.h>
 #include <stdint.h>
 
 #include <deque>