Fix the bluetooth audio device id changing on the fly issue and the active device inconsistent issu…

chromeos/audio/cras_audio_handler.cc

Index: chromeos/audio/cras_audio_handler.cc
diff --git a/chromeos/audio/cras_audio_handler.cc b/chromeos/audio/cras_audio_handler.cc
index 5460466c4b5ef0c94a972b04e4e7f5975888ffad..60663eb5be52041ad872be1598f34d7180c84e55 100644
--- a/chromeos/audio/cras_audio_handler.cc
+++ b/chromeos/audio/cras_audio_handler.cc
@@ -30,6 +30,11 @@ const int kMuteThresholdPercent = 1;
 
 static CrasAudioHandler* g_cras_audio_handler = NULL;
 
+bool IsSameAudioDevice(const AudioDevice& a, const AudioDevice& b) {
+  return a.id == b.id && a.is_input == b.is_input && a.type == b.type

[rkc, 2013/09/16 22:38:11]

Shouldn't just comparing the id's be enough? IIRC, the device ID we get up to
Chrome is an OR of (device_id << 32 | node_id), which should make it unique?

[jennyz, 2013/09/16 22:47:03]

I am being extra careful here, after observing cras may behave unexpectedly in
some cases. This should not happen, but I am guarding it carefully just in case.

+      && a.device_name == b.device_name;
+}
+
 }  // namespace
 
 CrasAudioHandler::AudioObserver::AudioObserver() {
@@ -562,12 +567,31 @@ bool CrasAudioHandler::HasDeviceChange(const AudioNodeList& new_nodes,
 
   for (AudioNodeList::const_iterator it = new_nodes.begin();
        it != new_nodes.end(); ++it) {
-    if (is_input == it->is_input)
+    if (is_input == it->is_input) {
       ++num_new_devices;
+      // Look to see if the new device not in the old device list.
+      AudioDevice device(*it);
+      if (FoundNewDevice(device))
+        return true;
+    }
   }
   return num_old_devices != num_new_devices;
 }
 
+bool CrasAudioHandler::FoundNewDevice(const AudioDevice& device) {
+  const AudioDevice* device_found = GetDeviceFromId(device.id);
+  if (!device_found)
+    return true;
+
+  if (!IsSameAudioDevice(device, *device_found)) {
+    LOG(WARNING) << "Different Audio devices with same id:"
+        << " new device: " << device.ToString()
+        << " old device: " << device_found->ToString();
+    return true;
+  }
+  return false;
+}
+
 void CrasAudioHandler::UpdateDevicesAndSwitchActive(
     const AudioNodeList& nodes) {
   size_t old_audio_devices_size = audio_devices_.size();