Fix compilation error in random-number-generator.cc

Bug: 
Change-Id: If8994168c72d1f6425f1b5f5a33cecdcc34ad3aa
Reviewed-on: https://chromium-review.googlesource.com/763287Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49389}

src/base/utils/random-number-generator.cc

@@ -132,7 +132,7 @@ std::vector<uint64_t> RandomNumberGenerator::NextSample(uint64_t max,
   CHECK_LE(n, max);
 
   if (n == 0) {
-    return {};
+    return std::vector<uint64_t>();
   }
 
   // Choose to select or exclude, whatever needs fewer generator calls.