Revert of Remove various IDs (patchset #7 id:120001 of https://codereview.webrtc.org/3019543002/ )

Reason for revert:
Breaks downstream

Original issue's description:
> Remove various IDs:
>
> - AudioFrame
> - AudioCodingModule
>
> BUG=webrtc:4690
> TBR=kwiberg@webrtc.org
>
> Review-Url: https://codereview.webrtc.org/3019543002
> Cr-Commit-Position: refs/heads/master@{#20005}
> Committed: https://webrtc.googlesource.com/src/+/2d0f77585d556d8b11d6269d35149ae9ca14c472

TBR=henrik.lundin@webrtc.org,kwiberg@webrtc.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=webrtc:4690

Review-Url: https://codereview.webrtc.org/3014683002
Cr-Commit-Position: refs/heads/master@{#20008}
diff --git a/modules/audio_coding/include/audio_coding_module.h b/modules/audio_coding/include/audio_coding_module.h
index 63af3ab..944ad60 100644
--- a/modules/audio_coding/include/audio_coding_module.h
+++ b/modules/audio_coding/include/audio_coding_module.h
@@ -70,6 +70,7 @@
     Config(const Config&);
     ~Config();
 
+    int id;
     NetEq::Config neteq_config;
     Clock* clock;
     rtc::scoped_refptr<AudioDecoderFactory> decoder_factory;
@@ -82,8 +83,8 @@
   // injected into ACM. ACM will take the ownership of the object clock and
   // delete it when destroyed.
   //
-  static AudioCodingModule* Create();
-  static AudioCodingModule* Create(Clock* clock);
+  static AudioCodingModule* Create(int id);
+  static AudioCodingModule* Create(int id, Clock* clock);
   static AudioCodingModule* Create(const Config& config);
   virtual ~AudioCodingModule() = default;