addRandomColor makes infinite loop in some circumstances

[stanrocks]

There is an issue with "addRandomColor" method inside NewPaletteForm.js.

Required conditions:

1. User deleted all palettes but first one ("Material UI Colors"), which has only 19 colors or less;
2. User is adding colors to new palette with "random color" button only.

This will lead to situation, when there is no any unique color left (we need at least 20 unique colors to fill whole palette using "random color" button), "isDuplicateColor" will be truthful forever, while loop will run infinitely.

To fix that we need to store somewhere at least 20 unique colors at any point of time, even when there will be less than 20 colors in user's palettes, so those colors would always be available for "addRandomColor" method.

[NorthWillov]

#1 (comment)

This will fix an error, but it will be no longer picking colors from an existing palettes.

[ialnazer]

In App.js, line 59, when passing props to the NewPlaletteForm component, you can replace: palettes={this.state.palettes} with palettes={seedColors}.
This will guarantee that all colors are passed.

This is required as well in a situation where the user delete all palettes, which will cause an error when picking a random color from an empty array.