Updated structures and functions for setting the max bitrate limit to take rtc::Optional<int>

webrtc/api/webrtcsdp.cc

Index: webrtc/api/webrtcsdp.cc
diff --git a/webrtc/api/webrtcsdp.cc b/webrtc/api/webrtcsdp.cc
index 4a296d9ce2e28a274377e3ca79e727f45c5b6e91..ff68bda46e5026d98b6e58d86c15fdb8e23829b4 100644
--- a/webrtc/api/webrtcsdp.cc
+++ b/webrtc/api/webrtcsdp.cc
@@ -1291,9 +1291,9 @@ void BuildMediaDescription(const ContentInfo* content_info,
 
   // RFC 4566
   // b=AS:<bandwidth>
-  if (media_desc->bandwidth() >= 1000) {
+  if (media_desc->bandwidth() && (*media_desc->bandwidth() >= 1000)) {
     InitLine(kLineTypeSessionBandwidth, kApplicationSpecificMaximum, &os);
-    os << kSdpDelimiterColon << (media_desc->bandwidth() / 1000);
+    os << kSdpDelimiterColon << (*media_desc->bandwidth() / 1000);
     AddLine(os.str(), message);
   }
 
@@ -2553,6 +2553,12 @@ bool ParseContent(const std::string& message,
           if (!GetValueFromString(line, bandwidth, &b, error)) {
             return false;
           }
+          if (b < 0) {
+            std::ostringstream description;
+            description << "The bandwidth value must not be negative";
+            return ParseFailed(line, description.str(), error);
+          }
+
           // We should never use more than the default bandwidth for RTP-based
           // data channels. Don't allow SDP to set the bandwidth, because
           // that would give JS the opportunity to "break the Internet".
@@ -2564,7 +2570,7 @@ bool ParseContent(const std::string& message,
                         << cricket::kDataMaxBandwidth / 1000 << "kbps.";
             return ParseFailed(line, description.str(), error);
           }
-          media_desc->set_bandwidth(b * 1000);
+          media_desc->set_bandwidth(rtc::Optional<int>(b * 1000));
         }
       }
       continue;