Refactoring text layer builder and converting text layer builder to a class

[timvandermeij]

This work is needed for cleaning up the text layer and for separating the text layer builder from the PDF find controller. This PR consists of four commits for easier reviewing.

The first commit:

• fixes code style and properly names functions;
• moves constants to the top of the file;
• reduces unnecessary typeof usage;
• caches loop variables;
• reduces unnecessary in usage;
• uses strict equalities where possible;
• removes an old TODO;
• uses more descriptive variable names;
• removes the highlightDiv and appendText functions as appendText was just a direct call to appendTextToDiv and highlightDiv has been inlined because in code it is clear what is does, so this saves some function calls.

The second commit:

• converts the text layer builder to a class.

The third commit:

• refactors PDFFindController in the text layer builder, thereby removing the last typeof in this file.

The fourth commit:

• updates the text selection example to remove unnecessary includes.

[Snuffleupagus]

I'm not sure if it matters in this particular instance, but these expressions aren't actually equal. It needs to be: textDiv.dataset.isWhitespace !== undefined (or textDiv.dataset['isWhitespace'] !== undefined).

[timvandermeij]

I think it does not matter in this case, but to be sure to not change the viewer's behavior I will change it. Thanks!

[timvandermeij]

Done in new commit.

[yurydelendik]

can you refactor it to be in the following format:

var TextLayerBuilder = (function TextLayerBuilderClosure() {
  function TextLayerBuilder(options) { ... }
  TextLayerBuilder.prototype = {
    ...
    renderMatches: function TextLayerBuilder_renderMatches(matches) {
    },
    ...
  };
  return TextLayerBuilder;
})();

After that it's easy step/commit to replace PDFFindController to this.findController

[timvandermeij]

/botio-linux preview

[pdfjsbot]

From: Bot.io (Linux)

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[pdfjsbot]

From: Bot.io (Linux)

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Full output at http://107.21.233.14:8877/3351d620a825bbb/output.txt

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Published

• Viewer: http://107.21.233.14:8877/3351d620a825bbb/web/viewer.html
• B2G Viewer: http://107.21.233.14:8877/3351d620a825bbb/extensions/b2g/content/web/viewer.html
• Extension: http://107.21.233.14:8877/3351d620a825bbb/extensions/firefox/pdf.js.xpi
• Extension (AMO): http://107.21.233.14:8877/3351d620a825bbb/extensions/firefox/pdf.js.amo.xpi

[yurydelendik]

Looks good. Can you see if you can change text-selection example to remove findbar and findcontroller links?

[yurydelendik]

Thank you