Fixing off-by-one error with max SCTP id.

webrtc/api/datachannel.cc

Index: webrtc/api/datachannel.cc
diff --git a/webrtc/api/datachannel.cc b/webrtc/api/datachannel.cc
index 6b13bf2c705ae7152c9ce4fa6edef00f9ce92340..32da5355be79aa9203d1965d1c72a8eb65a6823b 100644
--- a/webrtc/api/datachannel.cc
+++ b/webrtc/api/datachannel.cc
@@ -31,7 +31,7 @@ bool SctpSidAllocator::AllocateSid(rtc::SSLRole role, int* sid) {
   int potential_sid = (role == rtc::SSL_CLIENT) ? 0 : 1;
   while (!IsSidAvailable(potential_sid)) {
     potential_sid += 2;
-    if (potential_sid > static_cast<int>(cricket::kMaxSctpSid)) {
+    if (potential_sid >= static_cast<int>(cricket::kMaxSctpStreams)) {

[pthatcher1, 2016/08/22 23:09:30]

I liked the way it read before: "if sid > maxSid { return false; }".  

[Taylor Brandstetter, 2016/08/23 00:53:14]

Done.

       return false;
     }
   }
@@ -57,7 +57,7 @@ void SctpSidAllocator::ReleaseSid(int sid) {
 }
 
 bool SctpSidAllocator::IsSidAvailable(int sid) const {
-  if (sid < 0 || sid > static_cast<int>(cricket::kMaxSctpSid)) {
+  if (sid < 0 || sid >= static_cast<int>(cricket::kMaxSctpStreams)) {
     return false;
   }
   return used_sids_.find(sid) == used_sids_.end();