[libFuzzer][Windows] Fix template_url_parser_fuzzer build

Use uniform_int_distribution in a way that Windows allows.

Bug: 891867
Change-Id: I7a9cf5c213ddfc8ca83efa29757674eea54a1c44
Reviewed-on: https://chromium-review.googlesource.com/c/1260162
Commit-Queue: Jonathan Metzman <metzman@chromium.org>
Reviewed-by: Martin Barbella <mbarbella@chromium.org>
Cr-Commit-Position: refs/heads/master@{#596424}

testing/libfuzzer/fuzzers/template_url_parser_fuzzer.cc

@@ -21,12 +21,15 @@ class PseudoRandomFilter : public TemplateURLParser::ParameterFilter {
   ~PseudoRandomFilter() override = default;
 
   bool KeepParameter(const std::string&, const std::string&) override {
-    return pool_(generator_);
+    // Return true 254/255 times, ie: as if pool_ only returned uint8_t.
+    return pool_(generator_) % (UINT8_MAX + 1);
   }
 
  private:
   std::mt19937 generator_;
-  std::uniform_int_distribution<uint8_t> pool_;
+  // Use a uint16_t here instead of uint8_t because uniform_int_distribution
+  // does not support 8 bit types on Windows.
+  std::uniform_int_distribution<uint16_t> pool_;
 };
 
 struct FuzzerFixedParams {