private synchronized byte[] allocateByteArray(int size) {
    // Start with clearing reference and releasing currently owned byte array
    mByteArraySoftRef.clear();
    byte[] byteArray = new byte[size];
    mByteArraySoftRef.set(byteArray);
    return byteArray;
  }
Responds to memory pressure by simply 'discarding' the local byte array if it is not used at
the moment.

@param trimType kind of trimming to perform (ignored)
imagepipeline/src/main/java/com/facebook/imagepipeline/memory/SharedByteArray.java