app_server: Fixed build with tracing enabled.
app_server: Fixed issues in Painter.

 * DrawPolygon was offsetting coords to pixel centers
   regardless of whether the polygon was stroked or
   filled, leading to wrong results for filling. Now
   it offsets for stroking only and even takes pen-size
   into acount. The bug was visible in Gobe Productive's
   selection rendering.
 * Renamed _Transform() methods to _Align(), which fits
   better with what they do: Align coordinates with the
   pixel grid.
 * Changed rounding behavior for StrokeLine. Offsetting
   to pixel centers depending on pen-size happens regardless
   of sub-pixel mode. This means a stroked line on integer
   coordinates looks the same in both modes. It breaks
   some drawing in WonderBrush (brush cursor), which was
   exploiting the previous behavior, but unbreaks Gobe
   Productive caret rendering at zoom levels below 150%.

Both changes bring Gobe Productive text editing to a useable
level.
ScreenSaver: Refactor ModulesView

Create controls in initializer list of constructor, delete controls in
the (newly-added) destructor.

Make fSettings the first private member.
ScreenSaver: Add "No preview available" text

... when a screensaver doesn't provide a preview.

Also do a bit of refactoring in PreviewView, remove unneeded includes
Fix spinlock usage in kernel's system profiling

* Removal of gSchedulerLock left a few SpinLockers around which were
  now without locked interrupts.

* Makes scheduling_recorder work again.
radeon_hd: Clean up DP training

* Few tweaks to DP training
* Check for TP3 support and go with TP3 if needed
* Make training more verbose
* Fix DP snoose on ce