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 93d4acc6c3fad5fd2e2612ff22af02de2554baeb..f74485e5bfa949b3ac5c758de5097fa0844ce696 100644
--- a/webrtc/api/webrtcsdp.cc
+++ b/webrtc/api/webrtcsdp.cc
@@ -1297,9 +1297,9 @@ 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);
   }
 
@@ -2558,22 +2558,28 @@ bool ParseContent(const std::string& message,
         if (!GetValue(line, kApplicationSpecificMaximum, &bandwidth, error)) {
           return false;
         } else {
-          int b = 0;
-          if (!GetValueFromString(line, bandwidth, &b, error)) {
+          int bandwidth_value = 0;
+          if (!GetValueFromString(line, bandwidth, &bandwidth_value, error)) {
             return false;
           }
+          if (bandwidth_value < 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".
           // See: https://code.google.com/p/chromium/issues/detail?id=280726
           if (media_type == cricket::MEDIA_TYPE_DATA && IsRtp(protocol) &&
-              b > cricket::kDataMaxBandwidth / 1000) {
+              bandwidth_value > cricket::kDataMaxBandwidth / 1000) {
             std::ostringstream description;
             description << "RTP-based data channels may not send more than "
                         << cricket::kDataMaxBandwidth / 1000 << "kbps.";
             return ParseFailed(line, description.str(), error);
           }
-          media_desc->set_bandwidth(b * 1000);
+          media_desc->set_bandwidth(rtc::Optional<int>(1000 * bandwidth_value));
         }
       }
       continue;