todoItem should be deleted if updated text is blank

[hungtuchen]

as title said,
I think changing to this behavior would be better, only a minor fix

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[hungtuchen]

done!

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[andrewimm]

Sounds like a good change. Could you match the coding style of the rest of the repository by including spaces in the if and else lines, so that

if(this.state.editText){

becomes

if (this.state.editText) {

and

}else{

becomes

} else {

[hungtuchen]

done!

[andrewimm]

Thanks!