Replace uses of std::vector with SampleBuffer

As suggested in
https://github.com/mixxxdj/mixxx/pull/11120/files/e1db59ae2b4239a4beecdeb8f25020021e71d893#diff-1df0d6d18e318bf8be5dabd0990733f2130277c19452f13d50a05b6fd0527c34.

src/engine/bufferscalers/enginebufferscalerubberband.cpp

@@ -26,7 +26,7 @@ constexpr size_t kRubberBandBlockSize = 256;
 EngineBufferScaleRubberBand::EngineBufferScaleRubberBand(
         ReadAheadManager* pReadAheadManager)
         : m_pReadAheadManager(pReadAheadManager),
-          m_buffers{std::vector<CSAMPLE>(MAX_BUFFER_LEN), std::vector<CSAMPLE>(MAX_BUFFER_LEN)},
+          m_buffers{mixxx::SampleBuffer(MAX_BUFFER_LEN), mixxx::SampleBuffer(MAX_BUFFER_LEN)},
           m_bufferPtrs{m_buffers[0].data(), m_buffers[1].data()},
           m_interleavedReadBuffer(MAX_BUFFER_LEN),
           m_bBackwards(false),
@@ -297,8 +297,8 @@ void EngineBufferScaleRubberBand::reset() {
     // https://github.com/breakfastquay/rubberband/blob/c5f99d5ff2cba2f4f1def6c38c7843bbb9ac7a78/main/main.cpp#L652
     size_t remaining_padding = m_pRubberBand->getLatency();
 #endif
-    std::fill_n(m_buffers[0].begin(), kRubberBandBlockSize, 0.0f);
-    std::fill_n(m_buffers[1].begin(), kRubberBandBlockSize, 0.0f);
+    std::fill_n(m_buffers[0].span().begin(), kRubberBandBlockSize, 0.0f);
+    std::fill_n(m_buffers[1].span().begin(), kRubberBandBlockSize, 0.0f);
     while (remaining_padding > 0) {
         const size_t pad_samples = std::min<size_t>(remaining_padding, kRubberBandBlockSize);
         m_pRubberBand->process(m_bufferPtrs.data(), pad_samples, false);

src/engine/bufferscalers/enginebufferscalerubberband.h

@@ -3,10 +3,10 @@
 #include <rubberband/RubberBandStretcher.h>
 
 #include <array>
-#include <vector>
 
 #include "engine/bufferscalers/enginebufferscale.h"
 #include "util/memory.h"
+#include "util/samplebuffer.h"
 
 class ReadAheadManager;
 
@@ -61,14 +61,14 @@ class EngineBufferScaleRubberBand final : public EngineBufferScale {
     /// The audio buffers samples used to send audio to Rubber Band and to
     /// receive processed audio from Rubber Band. This is needed because Mixxx
     /// uses interleaved buffers in most other places.
-    std::array<std::vector<CSAMPLE>, 2> m_buffers;
+    std::array<mixxx::SampleBuffer, 2> m_buffers;
     /// These point to the buffers in `m_buffers`. They can be defined here
     /// since this object cannot be moved or copied.
     std::array<float*, 2> m_bufferPtrs;
 
     /// Contains interleaved samples read from `m_pReadAheadManager`. These need
     /// to be deinterleaved before they can be passed to Rubber Band.
-    std::vector<CSAMPLE> m_interleavedReadBuffer;
+    mixxx::SampleBuffer m_interleavedReadBuffer;
 
     // Holds the playback direction
     bool m_bBackwards;