Feed audio constraints over to WebRtcLocalAudioTrack

content/renderer/media/rtc_media_constraints.cc

Index: content/renderer/media/rtc_media_constraints.cc
diff --git a/content/renderer/media/rtc_media_constraints.cc b/content/renderer/media/rtc_media_constraints.cc
index 3988154912e75bf97ab32d18758ec64f5070dc31..69951c09a9ddfe3d7e0c5b4369d307b1fbed66f8 100644
--- a/content/renderer/media/rtc_media_constraints.cc
+++ b/content/renderer/media/rtc_media_constraints.cc
@@ -42,6 +42,8 @@ void GetNativeMediaConstraints(
 
 }  // namespace
 
+RTCMediaConstraints::RTCMediaConstraints() {}
+
 RTCMediaConstraints::RTCMediaConstraints(
       const WebKit::WebMediaConstraints& constraints) {
   if (constraints.isNull())
@@ -71,4 +73,21 @@ void RTCMediaConstraints::AddOptional(const std::string& key,
   optional_.push_back(Constraint(key, value));
 }
 
+bool  RTCMediaConstraints::AddMandatory(const std::string& key,
+                                        const std::string& value,
+                                        bool override_if_exists) {
+  for (Constraints::iterator iter = mandatory_.begin();
+       iter != mandatory_.end();
+       ++iter) {
+    if (iter->key == key) {
+      if (override_if_exists)
+        iter->value = value;
+      return override_if_exists;
+    }
+  }
+  // The key wasn't found, add it.
+  mandatory_.push_back(Constraint(key, value));
+  return true;
+}
+
 }  // namespace content