Redesign of the render buffering in AEC3

This CL centralizes the render buffering in AEC3 so that all render
buffers are updated and synchronized/aligned with the render alignment
buffer.

Bug: webrtc:8597, chromium:790905
Change-Id: I8a94e5c1f27316b6100b420eec9652ea31c1a91d
Reviewed-on: https://webrtc-review.googlesource.com/25680
Commit-Queue: Per Åhgren <peah@webrtc.org>
Reviewed-by: Gustaf Ullberg <gustaf@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#20989}

modules/audio_processing/aec3/render_delay_buffer.h

@@ -20,6 +20,7 @@
 #include "modules/audio_processing/aec3/downsampled_render_buffer.h"
 #include "modules/audio_processing/aec3/fft_data.h"
 #include "modules/audio_processing/aec3/render_buffer.h"
+#include "modules/audio_processing/include/audio_processing.h"
 
 namespace webrtc {
 
@@ -27,22 +28,28 @@ namespace webrtc {
 // extracted with a specified delay.
 class RenderDelayBuffer {
  public:
-  static RenderDelayBuffer* Create(size_t num_bands,
-                                   size_t down_sampling_factor,
-                                   size_t downsampled_render_buffer_size,
-                                   size_t render_delay_buffer_size);
+  enum class BufferingEvent {
+    kNone,
+    kRenderUnderrun,
+    kRenderOverrun,
+    kApiCallSkew,
+    kRenderDataLost
+  };
+
+  static RenderDelayBuffer* Create(const EchoCanceller3Config& config,
+                                   size_t num_bands);
   virtual ~RenderDelayBuffer() = default;
 
-  // Resets the buffer data.
+  // Resets the buffer alignment.
   virtual void Reset() = 0;
 
-  // Inserts a block into the buffer and returns true if the insert is
-  // successful.
-  virtual bool Insert(const std::vector<std::vector<float>>& block) = 0;
+  // Inserts a block into the buffer.
+  virtual BufferingEvent Insert(
+      const std::vector<std::vector<float>>& block) = 0;
 
   // Updates the buffers one step based on the specified buffer delay. Returns
-  // true if there was no overrun, otherwise returns false.
-  virtual bool UpdateBuffers() = 0;
+  // an enum indicating whether there was a special event that occurred.
+  virtual BufferingEvent PrepareCaptureCall() = 0;
 
   // Sets the buffer delay.
   virtual void SetDelay(size_t delay) = 0;
@@ -50,6 +57,12 @@ class RenderDelayBuffer {
   // Gets the buffer delay.
   virtual size_t Delay() const = 0;
 
+  // Gets the buffer delay.
+  virtual size_t MaxDelay() const = 0;
+
+  // Gets the observed jitter in the render and capture call sequence.
+  virtual size_t MaxApiJitter() const = 0;
+
   // Returns the render buffer for the echo remover.
   virtual const RenderBuffer& GetRenderBuffer() const = 0;