We're already, since quite some time, using the standard Fullscreen API provided that it's available in the browser. The warning is only caused by the code that checks if the Fullscreen API is supported.
This patch uses a simple preprocessor tag to avoid the warning, since I'm assuming that in general, we want to try and remain backwards compatible with the prefixed versions of the Fullscreen API.
Fixes 7270.
Multiple shadow roots are not supported any more in Chrome 51+
(https://crbug.com/603448#c6), so this patch changes the way that PDFs
are rendered in `<embed>` / `<object>` tags.
I used shadow roots because their content is not visible from the web
page, so the odds of conflicts were minimal. Now I have to render the
PDF frame directly in the page, which can be observed from the page
(unfortunately).
Now the following happens when an embedded PDF tag is detected:
- `<embed>` tags: The type and src attributes are updated.
- `<object>` tags: The type attribute is changed and the fallback
content is set and displayed.
When Firefox is run in e10s mode, which will soon be the default, the PDF.js zoom dropdown menu doesn't look right. This is apparently because the `<select>` DOM element is rendered in the parent, and that all the necessary style information isn't sent up from the child. See the discussion in https://bugzilla.mozilla.org/show_bug.cgi?id=910022.
Besides this causing the PDF.js UI to *look* worse in e10s, notably it also means that the `customScaleOption` isn't hidden like it ought to be.
To work-around that, this patch utilizes the `hidden` attribute, since https://bugzilla.mozilla.org/show_bug.cgi?id=1242450 at least made that work in e10s.
Fixes https://bugzilla.mozilla.org/show_bug.cgi?id=1194700.
This naming issue has been present since PR 3529, but at least I cannot find any issues/bugs that seem to have been caused by it, which is good.
The patch also removes an unnecessary `else` branch, since an already existing `break` means that it's redundant.
Fixes 7232.
Furthermore we introduce two new methods named `setCallback` and
`setReason` so external code does not change the properties of the class
directly. Finally we update various names of properties and methods to
be more self-explanatory.
