Function DoStringTrim

base/string/algorithm.cpp:487–502

template <typename StringType>
static void DoStringTrim(StringType* str)
{
    size_t start_pos = 0;
    size_t end_pos = str->length();
    while (start_pos != end_pos && isspace((*str)[start_pos]))
        start_pos++;
    if (start_pos == end_pos)
    {
        str->clear();
        return;
    }
    end_pos--;
    while (isspace((*str)[end_pos])) // end_pos always >= 0
        end_pos--;
    *str = str->substr(start_pos, end_pos - start_pos + 1);
}

void StringTrim(std::string* str)
{