media: Enable video decode acceleration through VAAPI

This CL enables H.264 codec video decode, leveraged by VAAPI. This work was
originally made for Crosswalk runtime by Qing Zhang <qing.zhang@intel.com> and
now been ported here with many additional changes.

The commands used to download, build and test libva:

  git clone git://anongit.freedesktop.org/libva
  cd libva/
  git checkout libva-1.2.1
  ./autogen.sh --prefix=$WLD  # you need to set your installation prefix here
  make -j4 && make install

  cd ../
  git clone git://anongit.freedesktop.org/vaapi/intel-driver
  cd intel-driver/
  git checkout 1.2.1
  ./autogen.sh --prefix=$WLD  # you need to set your installation prefix here
  make -j4 && make install

then on Chromium side, targets have to be build with something like:

  export GYP_DEFINES='chromeos=0 use_ozone=1 proprietary_codecs=1 ffmpeg_branding=Chrome'
  ninja -j16 -C out/Release content

and to run:
  ~/git/chromium/src/out/Release$ ./content_shell --no-sandbox --user-data-dir=/tmp/chrome --ignore-gpu-blacklist ../../third_party/WebKit/PerformanceTests/resources/bear-1280x720.mp4  --vmodule=*/ozone/ui*=3 --v=0

additionally, you can start content_shell with --disable-accelerated-video-decode
to compare the results.
patches: Add Media Ozone Platform support

This patch was already committed upstream and has to be removed once gardening
takes place:

https://codereview.chromium.org/269673005/
patches: Add remaining upstream patches

These patches were lacking in the previous commit. They also will need to get
removed once Chromium version gets updated in here.
Gardening: Update to latest revision.
Enable support for Ash.

Support for ASH is part of Chromium-X11 and we should start using it by
default. This CL adds needed support for enabling ASH and also updated
the README instructions.
Media: Remove un-used wl_display in TFPPicture.
Media: Avoid initializing display connection in VaapiVideoDecodeAccelerator.

VaapiVideoDecodeAccelerator initializes a new Wayland Display connection,
instead it should try to reuse the already existing Display connection.
This patch changes it so that VaapiVideoDecodeAccelerator queries native
display via GetPlatformDefaultEGLNativeDisplay and uses it.
[RPM] Remove X-Window dependencies
[RPM] Add weston as BuildRequires
Gardening: Update to latest revision.
Gardening: Adopt to https://codereview.chromium.org/312393002/
Gardening: Adopt to https://codereview.chromium.org/341253002/
Delete OzoneChannelHostFactory.

OzoneChannelHostFactory is not used anymore. This CL removes this
class.
Move everything under content to ui namespace.
Move everything related to events from content to ui/events.
Move everything under content/ to ui/public
Fix coding style.
Media: Fix shared component build.
Temporarily disable HWA decoding support.

Issue: https://github.com/01org/ozone-wayland/issues/240
Update patch script with correct branch no.