[test] Make it more likely to use smaller interrupt-budget on fuzzer

TBR=sergiyb@chromium.org
NOTRY=true

Bug: v8:6917
Change-Id: Ie585754c84f42cd864ab3b161a1ae27f7c2d2ab5
Reviewed-on: https://chromium-review.googlesource.com/899303Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Reviewed-by: Sergiy Byelozyorov <sergiyb@chromium.org>
Commit-Queue: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/master@{#51070}

tools/testrunner/testproc/fuzzer.py

@@ -220,7 +220,8 @@ class CompactionFuzzer(Fuzzer):
 class InterruptBudgetFuzzer(Fuzzer):
   def create_flags_generator(self, rng, test, analysis_value):
     while True:
-      yield ['--interrupt-budget=%d' % rng.randint(1, 144 * 1024)]
+      limit = 1 + int(rng.random() * 144)
+      yield ['--interrupt-budget=%d' % rng.randint(1, limit * 1024)]
 
 
 class DeoptAnalyzer(Analyzer):