[ Merge of http://go/wvgerrit/82232 ] The new function `ArraySize` will only work for compile-time fixed-length arrays, and will provide compiler errors if the provided argument is not an array. This will replace the commonly used macro `N_ELEM()` which uses `sizeof()`. Test: Linux unittest Bug: 137041745 Change-Id: I0f5c268197a8062a99ccba43c73349e97f66eb02