Extend net/base/parse_number.h for parsing of negative numbers, and determining if there was overflo

net/base/sdch_manager.cc

Index: net/base/sdch_manager.cc
diff --git a/net/base/sdch_manager.cc b/net/base/sdch_manager.cc
index 435977237d83d4856008b9c442bf3946f3c36091..78f7a01d17e61a361ea59147f8b2b238ed9e50be 100644
--- a/net/base/sdch_manager.cc
+++ b/net/base/sdch_manager.cc
@@ -382,7 +382,7 @@ SdchProblemCode SdchManager::AddSdchDictionary(
         expiration = base::Time::Now() + base::TimeDelta::FromSeconds(seconds);
       } else if (name == "port") {
         int port;
-        if (ParseNonNegativeDecimalInt(value, &port))
+        if (ParseIntegerBase10(value, false, &port, nullptr))
           ports.insert(port);
       }
     }