Update metadata sizes for Q2 2021 release
Update metadata sizes for Q2 2021 release

Transcribed (with tweaks) from PR #4986.

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