Return early if there's no block
Return early if there's no block

mark-friedman/blockly,nickmain/blockly,jstnhuang/blockly,nickmain/blockly,twodee/blockly,rachel-fenichel/blockly,rachel-fenichel/blockly,nickmain/blockly,mark-friedman/blockly,twodee/blockly,twodee/blockly,twodee/blockly,jstnhuang/blockly,nickmain/blockly,picklesrus/blockly,trinketapp/blockly,rachel-fenichel/blockly,picklesrus/blockly,trinketapp/blockly,twodee/blockly,trinketapp/blockly,nickmain/blockly,mark-friedman/blockly,mark-friedman/blockly,joshlory/blockly,rachel-fenichel/blockly,rachel-fenichel/blockly,nickmain/blockly,joshlory/blockly,twodee/blockly,jstnhuang/blockly,google/blockly,mark-friedman/blockly,trinketapp/blockly,rachel-fenichel/blockly,mark-friedman/blockly,google/blockly,google/blockly,rachel-fenichel/blockly,google/blockly,google/blockly,google/blockly,google/blockly,picklesrus/blockly,joshlory/blockly,jstnhuang/blockly