Fix random value of CachedReader at first time (#2556) #73

Job	Run time
gcc-compile-with-bazel	15m 52s
gcc-compile-with-boringssl	19m 59s
gcc-compile-with-cmake	2m 59s
clang-compile-with-bazel	13m 56s
clang-compile-with-boringssl	20m 13s
clang-compile-with-cmake	2m 37s
clang-compile-with-make	2m 50s
clang-compile-with-make-all-options	4m 48s
gcc-compile-with-bazel-all-options	18m 45s
gcc-compile-with-cmake-all-options	4m 59s
gcc-compile-with-make	2m 30s
gcc-compile-with-make-all-options	4m 17s
clang-compile-with-bazel-all-options	16m 40s
clang-compile-with-cmake-all-options	4m 27s
clang-unittest	14m 16s
	2h 29m 8s

Provide feedback