Remove skipping of creating of BLOCK_HEADER in preR13 #3235

Job	Run time
linux-cmake	7m 25s
linux (CFLAGS="-O0 -fno-omit-frame-pointer -fsanitize=address -fno-var-tracking" --disable-bindings)	4m 8s
linux (CC="clang")	9m 16s
linux (--enable-release)	10m 39s
linux (--enable-gcov --disable-bindings)	10m 21s
linux (--disable-write)	7m 49s
linux (CFLAGS="-O2 -m32" --disable-bindings)	5m 56s
linux (CFLAGS="-O2 -fno-omit-frame-pointer -fsanitize=undefined -fno-var-tracking" --disable-bind...	10m 41s
macOS	14m 32s
mingw	38m 22s
mingw-cmake	10m 39s
mips32-big-endian	19m 33s
ppc64-big-endian	11m 16s
vs2019	11m 10s
vs2019-ninja	8m 7s
	2h 59m 54s

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