[gn build] Port 005916d

Author: llvmgnsyncbot

llvm/utils/gn/secondary/libcxx/include/BUILD.gn

@@ -78,6 +78,7 @@ if (current_toolchain == default_toolchain) {
       "__algorithm/copy.h",
       "__algorithm/copy_backward.h",
       "__algorithm/copy_if.h",
+      "__algorithm/copy_move_common.h",
       "__algorithm/copy_n.h",
       "__algorithm/count.h",
       "__algorithm/count_if.h",