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# Googleへのプルリク

## The basics

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- [x] I branched from develop
- [x] My pull request is against develop
- [x] My code follows the [style guide](https://developers.google.com/blockly/guides/modify/web/style-guide)

## The details
### Resolves

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N/A

### Proposed Changes

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The only current-executed blocks should be highlighted but are not cleared so finally all the blocks are lit on only when they run the program on IE10/11.


### Reason for Changes

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In Japan many online materials of STEM classes for elementary schools are based on Google Blockly, so the case where children use Goolgle Blockly is not rare. Moreover most of Japanese schools are not equipped with Chrome/ Microsoft Edge nor Safari. They use Internet Explorer, even though IE has not supported.
We would like to make it clear to children that which code is to debag.

https://blockly-demo.appspot.com/static/demos/interpreter/step-execution.html

### Test Coverage

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- or tell us how you tested it. For each systems you tested,
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Tested on:
* Desktop Chrome
* Desktop Firefox
* Desktop Safari
* Desktop Opera
* Windows Internet Explorer 10
* Windows Internet Explorer 11
* Windows Edge

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