Revert of [Mojo Video Capture] Adapt video_capture service to refactored video capture stack

media/capture/video/shared_memory_buffer_tracker.h

Index: media/capture/video/shared_memory_buffer_tracker.h
diff --git a/media/capture/video/shared_memory_buffer_tracker.h b/media/capture/video/shared_memory_buffer_tracker.h
index 1d10727262c689e3cfd85075b7a3f6595624e94b..bbca851336d9f9240e1ea993825852aefe8bc4fe 100644
--- a/media/capture/video/shared_memory_buffer_tracker.h
+++ b/media/capture/video/shared_memory_buffer_tracker.h
@@ -5,10 +5,11 @@
 #ifndef MEDIA_CAPTURE_VIDEO_SHARED_MEMORY_BUFFER_TRACKER_H_
 #define MEDIA_CAPTURE_VIDEO_SHARED_MEMORY_BUFFER_TRACKER_H_
 
-#include "media/capture/video/shared_memory_buffer_handle.h"
 #include "media/capture/video/video_capture_buffer_tracker.h"
 
 namespace media {
+
+class SharedMemoryBufferHandle;
 
 // Tracker specifics for SharedMemory.
 class SharedMemoryBufferTracker final : public VideoCaptureBufferTracker {
@@ -32,6 +33,24 @@
   size_t mapped_size_;
 };
 
+// A simple proxy that implements the BufferHandle interface, providing
+// accessors to SharedMemTracker's memory and properties.
+class SharedMemoryBufferHandle : public VideoCaptureBufferHandle {
+ public:
+  // |tracker| must outlive SimpleBufferHandle. This is ensured since a
+  // tracker is pinned until ownership of this SimpleBufferHandle is returned
+  // to VideoCaptureBufferPool.
+  explicit SharedMemoryBufferHandle(SharedMemoryBufferTracker* tracker);
+  ~SharedMemoryBufferHandle() override;
+
+  size_t mapped_size() const override;
+  uint8_t* data() override;
+  const uint8_t* data() const override;
+
+ private:
+  SharedMemoryBufferTracker* const tracker_;
+};
+
 }  // namespace media
 
 #endif  // MEDIA_CAPTURE_VIDEO_SHARED_MEMORY_BUFFER_TRACKER_H_