insert method
Implementation
void insert(int argb) {
final a = (argb * _HASH_MUL) & 0xffffffff;
final key = (a >> hashShift);
colors[key] = argb;
}
void insert(int argb) {
final a = (argb * _HASH_MUL) & 0xffffffff;
final key = (a >> hashShift);
colors[key] = argb;
}