[libFuzzer] make len_control less agressive: set the initial max len to the length of the largest seed. This was the original intent, but... Now, with a test, to ensure it stays this way

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@354191 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed