render: avoid left shifting negative values

It's undefined behavior.

Signed-off-by: Yuxuan Shui <[email protected]>

v8.2

* Fixes assertion failures related to WIN_FLAGS_SHADOW_STALE, see yshui#479
* `write-pid-path` in configuration file now accepted
* Pid files are now deleted during shutdown
* Build fixes for certain platforms

v8.1

Fixed yshui#470 yshui#471 yshui#474 yshui#465

Worked around yshui#301

Fixed specifying a window id with the picom-trans script

Fixed minor memory leaks

config: remove xrender-sync

Deprecated since v5

Signed-off-by: Yuxuan Shui <[email protected]>

Update CONTRIBUTORS

Signed-off-by: Yuxuan Shui <[email protected]>

Changes

Only change since v7.4 is the rename from `compton` to `picom`, which is
backported from the `next` branch.

As a user, you don't need to update to this version.

As a distro packager, you should only package this version if you want
to adopt "picom" as the package name.

v7.4

- Fix several memory leaks, thanks to @liskin (yshui#236)

v7.3

- Build changes:
  - Vendor test.h so people building from the release tarballs doesn't
    have to clone that repository with git

v7.2:

- Fixes:
  - Stopped compton from sometimes freezing the X server when dbus is
    enabled.
  - Fixed the example dbus scripts.