[gtk] (8 commits) Non-fast-forward update to branch tracing

[Matthias Clasen <matthiasc src gnome org>]

The branch 'tracing' was changed in a way that was not a fast-forward update.
NOTE: This may cause problems for people pulling from the branch. For more information,
please see:

 https://wiki.gnome.org/Git/Help/NonFastForward

Commits removed from the branch:

  b684377... frame clock: Add minimal sysprof tracing
  f0539c4... profiler: Add an add_mark api
  3317c4c... gsk: Add a way to get time start time
  8a92de5... vulkan: Add tracing for the render time
  cf67ed2... gl: Add tracing for the render time
  55ba744... Add an fps counter
  681421b... Copy a fix from sysprof
  25ad652... Keep the capture writer object around
  70c92bc... Counter ids are unsigned
  9d6f116... Use the right file extension
  019fec0... fixup gl
  347583d... fixup vulkan
  8608fd8... fixup profiler
  d55164c... Add a counter api
  c137b85... Rejiggle the profiler api
  9867173... vulkan: Add pixel counters
  9033549... Add int counter api
  1e8b09c... fixup profiler
  90f5c58... fixup vulkan renderer`
  ba7f1b9... Remove duplicate counter definition
  4ca0a42... fix a compiler warning
  9fb6cbe... Fix times for fps counters
  335153a... fixup frame clock
  c42bd65... fixup vulkan
  d8ab107... fixup gl renderer
  5f19b95... rework activation of profiler
  4c944a9... fixup
  426ddf7... fixup to gdk.c
  e1fc90a... Add a dbus interface
  822fca9... hack widget-factory to be unique

Commits added to the branch:

  3301cc8... gdk: Add a profiler
  1bdc75a... Add a way to start the profiler
  e403cc5... frame clock: Add tracing
  b9ff8f5... gsk: Add some more profiler apis
  2e0c1e2... gsk: Add tracing to the gl renderer
  f7e64ea... gsk: Add tracing to the vulkan renderer
  768794a... GtkApplication: Add a profiler dbus api
  5842e46... Make widget-factory unique