fix #3596:Textarea of comment missing scrollbars (#4447)
fix #3596:Textarea of comment missing scrollbars (#4447)


rachel-fenichel/blockly,rachel-fenichel/blockly,google/blockly,mark-friedman/blockly,google/blockly,mark-friedman/blockly,google/blockly,google/blockly,rachel-fenichel/blockly,mark-friedman/blockly,mark-friedman/blockly,rachel-fenichel/blockly,rachel-fenichel/blockly,rachel-fenichel/blockly,google/blockly,rachel-fenichel/blockly,google/blockly,mark-friedman/blockly,mark-friedman/blockly,google/blockly