Android camera: use closest viewfinder resolution

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    if (m_captureMode.testFlag(QCamera::CaptureVideo) && m_camera->getPreferredPreviewSizeForVideo().isEmpty()) {
        // According to the Android doc, if getPreferredPreviewSizeForVideo() returns null, it means
        // the preview size cannot be different from the capture size
        adjustedViewfinderResolution = captureSize;
    } else {
        // search for viewfinder resolution with the same aspect ratio
        const qreal aspectRatio = qreal(captureSize.width()) / qreal(captureSize.height());
        QList<QSize> previewSizes = m_camera->getSupportedPreviewSizes();
        qreal minAspectDiff = 1;
        QSize closestResolution;
        for (int i = previewSizes.count() - 1; i >= 0; --i) {
            const QSize &size = previewSizes.at(i);
            const qreal sizeAspect = qreal(size.width()) / size.height();
            if (qFuzzyCompare(aspectRatio, sizeAspect)) {
                adjustedViewfinderResolution = size;
                break;
            } else if (minAspectDiff > qAbs(sizeAspect - aspectRatio)) {
                closestResolution = size;
                minAspectDiff = qAbs(sizeAspect - aspectRatio);
            }
        }

        if (!adjustedViewfinderResolution.isValid()) {
            qWarning("Cannot find a viewfinder resolution matching the capture aspect ratio.");
            if (closestResolution.isValid()) {
                adjustedViewfinderResolution = closestResolution;
                qWarning("Using closest viewfinder resolution.");
            } else {
                return;
            }
        }
    }
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