Merge "Use our glibc memset_explicit() polyfill." into main

    void* elems = env->GetPrimitiveArrayCritical(array, &isCopy);

    CHECK(!isCopy);

#ifdef __BIONIC__

    memset_explicit(elems, 0, buffer_size);

#else

    memset(elems, 0, buffer_size);

#endif

    // Clean the data cache so that the data gets zeroized in main memory right away.  Without this,

    // it might not be written to main memory until the cache line happens to be evicted.

    CleanDataCache(static_cast<const uint8_t*>(elems), buffer_size, cache_line_size);