[Extensions] Convert APIs to use movable types [1]

chrome/browser/extensions/api/audio_modem/audio_modem_api.cc

Index: chrome/browser/extensions/api/audio_modem/audio_modem_api.cc
diff --git a/chrome/browser/extensions/api/audio_modem/audio_modem_api.cc b/chrome/browser/extensions/api/audio_modem/audio_modem_api.cc
index 947e32399acdd54c248e344a2ded52bd53e6a16d..70c27ba8907e8f983c73f41361112f4c4dac31a7 100644
--- a/chrome/browser/extensions/api/audio_modem/audio_modem_api.cc
+++ b/chrome/browser/extensions/api/audio_modem/audio_modem_api.cc
@@ -226,16 +226,18 @@ void AudioModemAPI::WhispernetInitComplete(bool success) {
 
 void AudioModemAPI::TokensReceived(const std::vector<AudioToken>& tokens) {
   // Distribute the tokens to the appropriate app(s).
-  std::map<std::string, std::vector<linked_ptr<ReceivedToken>>> tokens_by_app;
+  std::list<ReceivedToken> all_tokens;
+  std::map<std::string, std::vector<ReceivedToken*>> tokens_by_app;
   for (const AudioToken& token : tokens) {
-    linked_ptr<ReceivedToken> api_token(new ReceivedToken);
+    ReceivedToken api_token;
     const std::string& raw_token = DecodeBase64Token(token.token);
-    api_token->token.assign(raw_token.c_str(),
-                            raw_token.c_str() + raw_token.size());
-    api_token->band = token.audible ? AUDIOBAND_AUDIBLE : AUDIOBAND_INAUDIBLE;
+    api_token.token.assign(raw_token.c_str(),
+                           raw_token.c_str() + raw_token.size());
+    api_token.band = token.audible ? AUDIOBAND_AUDIBLE : AUDIOBAND_INAUDIBLE;
+    all_tokens.push_back(std::move(api_token));
     for (const auto& receiver :
          receive_timers_[token.audible ? AUDIBLE : INAUDIBLE]) {
-      tokens_by_app[receiver.first].push_back(api_token);
+      tokens_by_app[receiver.first].push_back(&all_tokens.back());
     }
   }
 
@@ -246,11 +248,21 @@ void AudioModemAPI::TokensReceived(const std::vector<AudioToken>& tokens) {
     if (app_id.empty())
       continue;
 
+    // Construct the event arguments by hand because the generated version
+    // takes a std::vector<ReceivedToken>, but we use a
+    // std::vector<ReceivedToken> since the same token can go to multiple

[asargent_no_longer_on_chrome, 2016/03/30 19:39:24]

Something in this comment isn't quite right, or at least I'm confused about what
you're trying to say here. The thing I can't quite wrap my head around is "the
generated version takes std::vector<ReceivedToken>..." but you then say "we use
"std::vector<ReceivedToken>..." which is the same type. Can you fix or clarify?

Also, the code in this method is kind of confusing because |tokens| inside this
for loop shadows the function argument named |tokens|. Mind fixing that while
you're in here?

[Devlin, 2016/03/30 22:23:43]

Heh whoops.  One of those was supposed to be a std::vector<ReceivedToken*>. I've
rephrased the comment to (hopefully) make it less confusing.

Also renamed tokens to app_tokens.

+    // listeners.
+    scoped_ptr<base::ListValue> tokens_value(new base::ListValue());
+    for (const ReceivedToken* token : tokens)
+      tokens_value->Append(token->ToValue());
+    scoped_ptr<base::ListValue> args(new base::ListValue());
+    args->Append(std::move(tokens_value));
+
     EventRouter::Get(browser_context_)
         ->DispatchEventToExtension(
             app_id, make_scoped_ptr(new Event(events::AUDIO_MODEM_ON_RECEIVED,
                                               OnReceived::kEventName,
-                                              OnReceived::Create(tokens))));
+                                              std::move(args))));
   }
 }