Dialog: Don't reset symbol keys after onClickButton

* Resetting the keys makes typing a URL, SMB, FTP or any address
    a longer process than is necessary, especially with a remote.

Signed-off-by: Brandon McAnsh <brandonm@matricom.net>
CGUIDialogSettingsBase: fix default control overriding (only override if it hasn't been set by the skin or is invalid; fixes 15479)
[gtests] disable Event.GroupLimitedGroupScope till somebody fixes it
Merge pull request #5508 from wsnipex/fix-gtests

[gtests] disable Event.GroupLimitedGroupScope till somebody fixes it
Merge pull request #5475 from Matricom/removesymbolreset

Dialog: Don't reset symbol keys after onClickButton
Merge pull request #5501 from Montellese/settings_fix_default_control

CGUIDialogSettingsBase: fix default control overriding
[rbp/omxplayer] When opening a stream don't try to update gui so often
[ffmpeg] Speed up wtv index creation

The index creation is O(N^2) with number of entries (typically thousands).
On a Pi this can take more than 60 seconds to execute for a recording of a few hours.

By replacing with an O(N) loop, this takes virtually zero time
adds GetTvShowSeasons
move AddSeason() public.
adds GetArt function to (video) scraper, allowing art to be fetched given the video identifier.
refresh season art if a new season is found that isn't recorded in the database yet. Fixes #14339
REMOVEME: updated thetvdb.com scraper to support art updates
[omx] Report decoded image name
logging: Add microsecond timer to log messages
videoplayer: adapt lateness detection and dropping to buffering
video player: present correct pts to user for a/v sync (after buffering in renderer)
[hifiberry] Hack: force it to be recognised as IEC958 capable to enable passthrough options
Move the reference-counting of Begin and End calls from DX and GL source files into GUIFontTTF.cpp.
Convert CGUIFontTTFBase::m_vertex to be managed as a std::vector.

Also retired CGUIFontTTFBase::m_vertex_count and
CGUIFontTTFBase::m_vertex_size because these can be derived from vector
member functions.