Merge "libvulkan: avoid allocation if final extension count is zero"

        const char** names;

        uint32_t name_count;

        ExtensionFilter()

            : exts(nullptr), ext_count(0), names(nullptr), name_count(0) {}

    };

    VkResult SanitizeApiVersion();

    } else {

        count = std::min(filter.ext_count, dev_info_.enabledExtensionCount);

    }

    if (!count)

        return VK_SUCCESS;

    filter.names = reinterpret_cast<const char**>(allocator_.pfnAllocation(

        allocator_.pUserData, sizeof(const char*) * count, alignof(const char*),

        VK_SYSTEM_ALLOCATION_SCOPE_COMMAND));