Allow audio debug recordings through a private API extension.

chrome/common/extensions/api/webrtc_logging_private.idl

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Use the <code>chrome.webrtcLoggingPrivate</code> API to control diagnostic
 // WebRTC logging.
 namespace webrtcLoggingPrivate {
   dictionary MetaDataEntry {
     // The meta data entry key.
     DOMString key;
@@ skipping 10 matching lines @@
   dictionary RequestInfo {
     // The tab identifier from the chrome.tabs API, if the request is from a
     // tab.
     long? tabId;
 
     // The guest process id for the requester, if the request is from a
     // webview.
     long? guestProcessId;
   };
 
+  // This contains information about the result of an AEC dump operation.
+  // didStop=false and isManualStop=false means startAecDump() was called

[Henrik Grunell, 2015/12/18 12:34:21]

Could these combinations be an enum(-ish variable) instead?

[Guido Urdaneta, 2015/12/18 18:38:58]

I tried it, but the problem is that the handler would need to know about this
enum, which did not look right.
However, I simplified the meanings of the boolean fields.

+  //     without a time limit.
+  // didStop=false and isManualStop=true means stopAecDump() was called, but no
+  //     AEC dump was in progress.
+  // didStop=true and isManualStop=false means an AEC Dump was stopped 
+  //     automatically due to hitting the time limit.
+  // didStop=true and isManualStop=true means an AEC Dump was stopped by a call
+  //     to stopAecDump().
+  dictionary AecDumpInfo {

[Henrik Grunell, 2015/12/18 12:34:21]

Rename "AecDump" to "AudioDebugRecordings" everywhere. AEC dump is only one part
that's being enabled.

[Guido Urdaneta, 2015/12/18 18:38:58]

Done.

+    // Indicates if an AEC dump was actually stopped.
+    boolean didStop;
+    // Indicates if a manual stop was attempted through a stopAecDump() call.
+    boolean isManualStop;
+    // Absolute path prefix for the AEC dump.
+    DOMString prefixPath;
+  };
+
+
   callback GenericDoneCallback = void ();
+  callback AecDumpCallback = void (AecDumpInfo info);
   callback UploadDoneCallback = void (UploadResult result);
 
   interface Functions {
     // For all functions, |request| determines which render process to apply
     // the operation on. |request| identifies the requesting process.
     // |securityOrigin| is the security origin for the tab identified by |tabId|
     // and is used for verifying that the tab is the correct one and has not
     // been navigated away from.
 
     // Sets additional custom meta data that will be uploaded along with the
@@ skipping 62 matching lines @@
                              GenericDoneCallback callback);
 
     // Stops RTP dumping. After stop has finished, the dumps will be
     // uploaded with the log if upload is called. Otherwise, the dumps will be
     // discarded.
     static void stopRtpDump(RequestInfo request,
                             DOMString securityOrigin,
                             boolean incoming,
                             boolean outgoing,
                             GenericDoneCallback callback);
+
+    // Starts an AEC Dump for all renderer processes with open peer connections.

[Henrik Grunell, 2015/12/18 12:34:21]

The more general description is that there's one file per APM, which happens to
be one per render process right now. This will likely change in the future. See
the description in webrtc internals. (Maybe point to that here to avoid
duplication.)

[Guido Urdaneta, 2015/12/18 18:38:58]

Given that we are now recording for a single process, I decided to simplify the
documentation instead.

+    // One file per renderer process will be created, with the renderer
+    // process ID appended to a predefined file path.
+    // |seconds| indicates how many seconds of audio to record. If |seconds| is
+    // zero, recording will continue until stopAecDump() is explicitly called.
+    // If |seconds| is negative, startAecDump() will fail.
+    // If |seconds| is zero |callback| is invoked immediately after the AEC
+    // dump starts. Otherwise, |callback| is invoked when the AEC dump is 
+    // stopped.
+    static void startAecDump(long seconds, AecDumpCallback callback);
+
+    // Stops all AEC Dumps for all renderer processes.
+    static void stopAecDump(AecDumpCallback callback);
   };
 };