Rename EncodedImage::_buffer --> buffer_, and make private

Bug: webrtc:9378
Change-Id: I0a0636077b270a7c73bafafb958132fa648aca70
Reviewed-on: https://webrtc-review.googlesource.com/c/117722
Reviewed-by: Karl Wiberg <kwiberg@webrtc.org>
Commit-Queue: Niels Moller <nisse@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#26294}
diff --git a/api/media_transport_interface.cc b/api/media_transport_interface.cc
index b5eaa89..c1a83bb 100644
--- a/api/media_transport_interface.cc
+++ b/api/media_transport_interface.cc
@@ -95,7 +95,7 @@
   referenced_frame_ids_ = o.referenced_frame_ids_;
   if (!encoded_data_.empty()) {
     // We own the underlying data.
-    encoded_image_._buffer = encoded_data_.data();
+    encoded_image_.set_buffer(encoded_data_.data(), encoded_data_.size());
   }
   return *this;
 }
@@ -110,8 +110,8 @@
   referenced_frame_ids_ = std::move(o.referenced_frame_ids_);
   if (!encoded_data_.empty()) {
     // We take over ownership of the underlying data.
-    encoded_image_._buffer = encoded_data_.data();
-    o.encoded_image_._buffer = nullptr;
+    encoded_image_.set_buffer(encoded_data_.data(), encoded_data_.size());
+    o.encoded_image_.set_buffer(nullptr, 0);
   }
   return *this;
 }
diff --git a/api/video/encoded_image.cc b/api/video/encoded_image.cc
index 994bf15..b093d1b 100644
--- a/api/video/encoded_image.cc
+++ b/api/video/encoded_image.cc
@@ -32,7 +32,7 @@
 EncodedImage::EncodedImage(const EncodedImage&) = default;
 
 EncodedImage::EncodedImage(uint8_t* buffer, size_t size, size_t capacity)
-    : _buffer(buffer), size_(size), capacity_(capacity) {}
+    : buffer_(buffer), size_(size), capacity_(capacity) {}
 
 void EncodedImage::SetEncodeTime(int64_t encode_start_ms,
                                  int64_t encode_finish_ms) {
diff --git a/api/video/encoded_image.h b/api/video/encoded_image.h
index 4828b02..717489f 100644
--- a/api/video/encoded_image.h
+++ b/api/video/encoded_image.h
@@ -75,12 +75,13 @@
   size_t capacity() const { return capacity_; }
 
   void set_buffer(uint8_t* buffer, size_t capacity) {
-    _buffer = buffer;
+    buffer_ = buffer;
     capacity_ = capacity;
   }
 
-  uint8_t* data() { return _buffer; }
-  const uint8_t* data() const { return _buffer; }
+  // TODO(bugs.webrtc.org/9378): When changed to owning the buffer, data() on a
+  // const object should return a const uint8_t*.
+  uint8_t* data() const { return buffer_; }
 
   uint32_t _encodedWidth = 0;
   uint32_t _encodedHeight = 0;
@@ -88,7 +89,6 @@
   int64_t ntp_time_ms_ = 0;
   int64_t capture_time_ms_ = 0;
   FrameType _frameType = kVideoFrameDelta;
-  uint8_t* _buffer;
   VideoRotation rotation_ = kVideoRotation_0;
   VideoContentType content_type_ = VideoContentType::UNSPECIFIED;
   bool _completeFrame = false;
@@ -112,6 +112,9 @@
   } timing_;
 
  private:
+  // TODO(bugs.webrtc.org/9378): Fix ownership. Currently not owning the data
+  // buffer.
+  uint8_t* buffer_;
   size_t size_;      // Size of encoded frame data.
   size_t capacity_;  // Allocated size of _buffer.
   uint32_t timestamp_rtp_ = 0;