When updating Preferences using the `set` method, the input is carefully validated. However, no validation is (currently) done when a `BasePreferences` instance is created, which probably isn't that great. Hence this patch that simply ignores, to not unnecessarily break loading of the viewer itself, any invalid Preferences.
Given that the various Preferences are currently, and have been for quite some time, only used when initializing `PDFViewerApplication` re-loading them when a new PDF file is opened in the viewer is essentially a no-op.
Furthermore, with the only usage of `BasePreferences.reload` now gone, the value of that method seems questionable at best. In the event that the functionality is actually needed again, similar to the `ViewHistory`, it'd probably make more sense to simply replace `PDFViewerApplication.preferences` with a new `BasePreferences` instance instead (using e.g. `DefaultExternalServices.createPreferences`).
Given that *all* Preferences are already fetched in `PDFViewerApplication._readPreferences`, the amount of boilerplate/duplication can be considerably reduced with the addition of a `BasePreferences.getAll` method.
This patch contains the following improvements:
- Only fetch the various document properties *once* per PDF file opened, and cache the result (in a frozen object).
- Always update the *entire* dialog at once, to prevent inconsistent UI state (issue 8371).
- Ensure that the dialog, and all its internal properties, are reset when `PDFViewerApplication.close` is called.
- Inline, and re-factor, the `getProperties` method in `open`, since that's the only call-site.
- Always overwrite the fileSize with the value obtained from `pdfDocument.getDownloadInfo`, to ensure that it's correct.
- ES6-ify the code that's touched in this patch.
Fixes 8371.
Note that as discussed on IRC, this makes the viewer slightly slower to load *only* in `gulp server` mode, however the difference seem slight enough that I think it will be fine.
The sidebar code has, except for minor fixes/additions (such as attachments), been largely untouch for years.
To avoid having a bunch of sidebar code sprinkled throughout viewer.js, this patch moves the sidebar code into a separate file (pdf_sidebar.js), similar to how most other functionality has been moved in the last few years.
Besides simply moving code around, this patch also has the added benefit that we now keep track of the sidebar state (not just opened/closed).
This now makes it possible to handle both `Preferences` *and* `ViewHistory` settings for the sidebar state in a cleaner way, preventing strange and confusing interactions between the two.
