fix:to fixed ToolbarOption is undenfined

[chenlang0311]

Summary

What kind of change does this PR introduce? (check at least one)

• Bugfix
• Feature
• Code style update
• Refactor
• Docs
• Build-related changes
• Other, please describe:

If changing the UI of default theme, please provide the before/after screenshot:

Does this PR introduce a breaking change? (check one)

• Yes
• No

If yes, please describe the impact and migration path for existing applications:

The PR fulfills these requirements:

• When resolving a specific issue, it's referenced in the PR's title (e.g. fix #xxx[,#xxx], where "xxx" is the issue number)

You have tested in the following browsers: (Providing a detailed version will be better.)

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If adding a new feature, the PR's description includes:

• A convincing reason for adding this feature
• Related documents have been updated
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To avoid wasting your time, it's best to open a feature request issue first and wait for approval before working on it.

Other information:

[codecov-commenter]

Codecov Report

Merging #473 (31276b5) into master (394c3f1) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #473   +/-   ##
=======================================
  Coverage   75.89%   75.89%           
=======================================
  Files           8        8           
  Lines        1419     1419           
=======================================
  Hits         1077     1077           
  Misses        342      342           

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[chenlang0311]

使用最新版本1.9.1.当项目中使用了TS的时候，打包的时候会报错，错误如图

[fengyuanchen]

What's your configure for the Viewer class?

[chenlang0311]

What's your configure for the Viewer class?

No other options, the options is the defaut, you can see the v-viewer, we are use the package.

new Viewer(el, { inline: false, filter: filterImage, url: filterSrc })
function filterImage(image) {
  return image.getAttribute('data-viewer');
}
function filterSrc(image) {
  return image.getAttribute('data-src');
}