Reduce the fuzzer program fanout limit to 9.

Change-Id: I7bae28681165de0045a413d6fde69e058b17ba26
Reviewed-on: https://code-review.googlesource.com/9810
Reviewed-by: Paul Wankadia <junyer@google.com>
diff --git a/re2/fuzzing/re2_fuzzer.cc b/re2/fuzzing/re2_fuzzer.cc
index 6bf771f..f9326cf 100644
--- a/re2/fuzzing/re2_fuzzer.cc
+++ b/re2/fuzzing/re2_fuzzer.cc
@@ -21,9 +21,10 @@
     return;
 
   // Don't waste time fuzzing high-fanout programs.
+  // (They can also cause bug reports due to fuzzer timeouts.)
   std::map<int, int> histogram;
   int fanout = re.ProgramFanout(&histogram);
-  if (fanout > 10)
+  if (fanout > 9)
     return;
 
   StringPiece sp1, sp2, sp3, sp4;