Do not hash default and communications media device ID

content/public/browser/media_device_id.cc

Index: content/public/browser/media_device_id.cc
diff --git a/content/public/browser/media_device_id.cc b/content/public/browser/media_device_id.cc
index aefe67af541c120d993ca14d657794ee1d4d9d92..0d4971dce42762c32f10e92be9219b783ed3bd43 100644
--- a/content/public/browser/media_device_id.cc
+++ b/content/public/browser/media_device_id.cc
@@ -12,9 +12,24 @@
 
 namespace content {
 
+namespace {
+
+const char kDefaultDeviceId[] = "default";

[tommi (sloooow) - chröme, 2015/09/26 09:27:23]

Can we use the constants from media/ instead?
https://code.google.com/p/chromium/codesearch#chromium/src/media/audio/audio_...

[Guido Urdaneta, 2015/09/26 09:48:58]

I originally tried that, but, unfortunaetly, it is forbidden to #include
"media/" in content/public.

Maybe we should also expose these public/content constants and check that they
match the media constants somewhere?

[tommi (sloooow) - chröme, 2015/09/26 10:13:47]

Ah right. I didn't realize we're in public/.  Hmm... it's unfortunate that
content/ can't access media/ for the benefit of content/.  I think the actual
implementation of these methods needs to be moved into content (e.g. under
content/browser/media)

+const char kCommunicationsDeviceId[] = "communications";
+
+bool IsDefaultMediaDeviceID(const std::string& source_id) {
+  return (source_id == kDefaultDeviceId) ||

[tommi (sloooow) - chröme, 2015/09/26 09:27:24]

nit: () not necessary

[Guido Urdaneta, 2015/09/26 09:48:58]

Done.

+         (source_id == kCommunicationsDeviceId);
+}
+
+}  // namespace
+
 std::string GetHMACForMediaDeviceID(const ResourceContext::SaltCallback& sc,
                                     const GURL& security_origin,
                                     const std::string& raw_unique_id) {
+  if (IsDefaultMediaDeviceID(raw_unique_id))
+    return raw_unique_id;
+
   DCHECK(security_origin.is_valid());
   DCHECK(!raw_unique_id.empty());
   crypto::HMAC hmac(crypto::HMAC::SHA256);