Support for tracking focus rectangles in displayModels.
displayModel: track focus rects over scrolls and bitBlits (i.e. displayModel_t::copyRectangle knows about them).
A Papenmeier braille display can now be used even if a Papenmeier display has never been connected via USB.

Fixes #3712.
Gecko vbuf backend: Override the content with aria-label(ledby) where it makes sense; i.e. for elements where the content rendered is usually the same as the name such as links and buttons.
Gecko vbuf backend: Render the name of applications, dialogs and embedded objects so the user knows what they are without further investigation.

We don't render anything else for them, so we may as well render something useful.
Merge branch 't3888' into next. Incubates #3888
MSHTML vbuf backend: Override content with aria-label(ledby) where it makes sense, just as for Gecko.
Merge branch 't1354' into next

Incubates #1354.
NVDA no longer freezes when the Papenmeier BRAILLEX older models braille display is selected without a display connected.
In browse mode, labels on landmarks are now reported. They are also included in the Elements List dialog.
Merge branch 't1195' into next

Incubates #1195.
l10n:
From translation svn 14389.
Merge branch 'master' into next
In browse mode, labels on landmarks are now reported. They are also included in the Elements List dialog.
Initial work on support for the region role in browse mode.

Regions are treated as landmarks, but only if they are labelled. Also, the word "landmark" isn't reported, since this seems rather superfluous.
At present, reporting works correctly, but quick navigation will jump to unlabelled regions and the Elements List breaks when unlabelled regions are encountered.
When searching for a node by attributes in a virtual buffer, use regular expressions matching against a string of requested attributes.

This allows us to match against multiple, completely separate options without needing to write a complex custom query engine. It also allows for easier enhancement in future.
This is necessary to support regions as a landmark because normal landmarks don't need names but regions do.
When navigating by landmark, don't navigate to regions with no label.
Merge branch 't1195' into next

Incubates #1195.
Merge branch 't3741' into next

Incubates #3741.
Ensure that text copied to clipboard from displayModel contains line breaks.