Markdown: Fix UTF8 chars breaking elements

[nlepage]

Using UTF8 characters such as emojis in markdown input may create "offsets" in the HTML output and may even break UTF8 characters.

Example 1

With the following markdown:

## test
this is a test `🙂 this is a test` this is a test

HTML output is:

<google-codelab-step label="test" duration="0">
  <p>this is a test <code>🙂 this is </code>a test this is a test</p>
</google-codelab-step>

Example 2

With the following markdown:

## test
this is a test `this is a test 🙂` this is a test

HTML output is:

<google-codelab-step label="test" duration="0">
  <p>this is a test <code>�</code>��� this is a test</p>
</google-codelab-step>

Bug

splitSpaceRight() uses a rune index to split a string.

splitSpaceRight() and splitSpaceLeft() also have their final return reversed.

Fix

splitSpaceRight() now uses a byte index to split the string.

[jlandure]

Any news on this enhancement @jatorre @KeyboardNerd ? 👍

[mco-gh]

thanks!

[nlepage]

Just updated this to upstream's master:

• Unicode chars breaking was already fixed
• Kept the tests
• Return params of splitSpaceRight() and splitSpaceLeft() were still reversed...

@marcacohen I also had opened #367 but don't have time to update it, do whatever you want with it.

[mco-gh]

thanks!