Replace rtc::cricket::Settable with rtc::Maybe

talk/app/webrtc/videosource.cc

 /*
  * libjingle
  * Copyright 2012 Google Inc.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
  *
  *  1. Redistributions of source code must retain the above copyright notice,
  *     this list of conditions and the following disclaimer.
  *  2. Redistributions in binary form must reproduce the above copyright notice,
@@ skipping 249 matching lines @@
       best_diff_interval = diff_interval;
       best_it = it;
     }
   }
   return *best_it;
 }
 
 // Set |option| to the highest-priority value of |key| in the constraints.
 // Return false if the key is mandatory, and the value is invalid.
 bool ExtractOption(const MediaConstraintsInterface* all_constraints,
-    const std::string& key, cricket::Settable<bool>* option) {
+                   const std::string& key,
+                   rtc::Maybe<bool>* option) {
   size_t mandatory = 0;
   bool value;
   if (FindConstraint(all_constraints, key, &value, &mandatory)) {
-    option->Set(value);
+    *option = rtc::Maybe<bool>(value);
     return true;
   }
 
   return mandatory == 0;
 }
 
 // Search |all_constraints| for known video options.  Apply all options that are
 // found with valid values, and return false if any mandatory video option was
 // found with an invalid value.
 bool ExtractVideoOptions(const MediaConstraintsInterface* all_constraints,
@@ skipping 175 matching lines @@
 }
 
 void VideoSource::SetState(SourceState new_state) {
   if (VERIFY(state_ != new_state)) {
     state_ = new_state;
     FireOnChanged();
   }
 }
 
 }  // namespace webrtc