Change StunMessage::AddAttribute return type from bool to void.

webrtc/p2p/base/stun.h

Index: webrtc/p2p/base/stun.h
diff --git a/webrtc/p2p/base/stun.h b/webrtc/p2p/base/stun.h
index 153f63dc58665ef3a9322c7c2fb292f0b3e8b17b..028787c72aa9fd80c985bf156182803b221edcce 100644
--- a/webrtc/p2p/base/stun.h
+++ b/webrtc/p2p/base/stun.h
@@ -158,10 +158,8 @@ class StunMessage {
   const StunErrorCodeAttribute* GetErrorCode() const;
   const StunUInt16ListAttribute* GetUnknownAttributes() const;
 
-  // Takes ownership of the specified attribute, verifies it is of the correct
-  // type, and adds it to the message. The return value indicates whether this
-  // was successful.
-  bool AddAttribute(StunAttribute* attr);
+  // Takes ownership of the specified attribute and adds it to the message.
+  void AddAttribute(StunAttribute* attr);
 
   // Validates that a raw STUN message has a correct MESSAGE-INTEGRITY value.
   // This can't currently be done on a StunMessage, since it is affected by