Remove base's implicit_cast.

components/history/core/browser/history_backend.cc

Index: components/history/core/browser/history_backend.cc
diff --git a/components/history/core/browser/history_backend.cc b/components/history/core/browser/history_backend.cc
index ad61094c5702e56dddce0ef178a7d0071ac5969f..0a3252ed3a487ac66a0a21dc6c11c8baae0690e6 100644
--- a/components/history/core/browser/history_backend.cc
+++ b/components/history/core/browser/history_backend.cc
@@ -1367,7 +1367,7 @@ void HistoryBackend::QueryFilteredURLs(int result_count,
 
   // Limit to the top |result_count| results.
   std::sort(data.begin(), data.end(), PageUsageData::Predicate);
-  if (result_count && implicit_cast<int>(data.size()) > result_count)
+  if (result_count && static_cast<int>(data.size()) > result_count)

[vmpstr, 2015/09/11 21:00:49]

This should probably be either a saturated_cast or a checked_cast (or even
better QueryFilteredURLs might take a size_t for result_count, but I'm not sure
about what this code does and how set the signature is).

[danakj, 2015/09/11 21:20:28]

Changing the type seems a bit tricky, it does all the way through the history
stuff, down to places like
https://code.google.com/p/chromium/codesearch#chromium/src/components/history...

Where it clearly expects the range to be within an integer, so I don't want to
change assumptions naively.

I think the intent here is to have a positive integer-ranged value. So we can
cast the ints to size_t for the purpose of comparison and not get weird
truncation issues, and also make life easier for that TODO.

     data.resize(result_count);
 
   for (size_t i = 0; i < data.size(); ++i) {