Function toJSONString

Tests/DeltaTests.cc:28–30

static bool isValidUTF8(fleece::slice sl) noexcept;

static std::string toJSONString(const Value *v) {
    return v ? v->toJSONString() : "undefined";
}


static void checkDelta(const char *json1, const char *json2, const char *deltaExpected) {