Allow command key zoom on mac devices (#5419)
Allow command key zoom on mac devices (#5419)

* Allow command key zoom on mac devices

* Clarify comment on mac command key zoom
mark-friedman/blockly,google/blockly,rachel-fenichel/blockly,rachel-fenichel/blockly,rachel-fenichel/blockly,rachel-fenichel/blockly,google/blockly,rachel-fenichel/blockly,mark-friedman/blockly,rachel-fenichel/blockly,mark-friedman/blockly,rachel-fenichel/blockly,google/blockly,google/blockly,google/blockly,mark-friedman/blockly,mark-friedman/blockly,google/blockly,mark-friedman/blockly,google/blockly