in RenderScriptMigrationSample/app/src/main/cpp/VulkanResources.cpp [374:381]
bool Image::transitionLayout(VkImageLayout newLayout) {
if (newLayout == mLayout) return true;
VulkanCommandBuffer layoutCommand(mContext->device(), mContext->commandPool());
RET_CHECK(mContext->beginSingleTimeCommand(layoutCommand.pHandle()));
recordLayoutTransitionBarrier(layoutCommand.handle(), newLayout);
RET_CHECK(mContext->endAndSubmitSingleTimeCommand(layoutCommand.handle()));
return true;
}