app_server: missing null pointer check.

Should fix #16551.

app_server: don't reset brightness when switching workspaces

Fixes #16538.

app_server: save/restore screen brightness settings

The brightness is saved in the screen configurations of the first
workspace. For now, all screens get the same brightness (I can't get
screen IDs to work today). Since we only support setting the brightness
for laptop displays for now, this shouldn't matter. It can be fixed when
app_server gets actual multiple display support.

Fixes #14254

Change-Id: Ib33aa65a73407a65bd469d0efa8542210fec02d4
Reviewed-on: https://review.haiku-os.org/c/haiku/+/362
Reviewed-by: Adrien Destugues <pulkomandy@gmail.com>

app_server: match screen configurations with empty serial number

My laptop LCD has no serial number. Because of this check, it would
never "exact match" with the previous data stored in the workspace
settings. As a result, every time I set a new video mode, a new "screen"
would be stored in the settings file, and the old entry would just stay
there and never be used again.

I currently find myself with about 100K of workspace settings, tracing
the history of video mode changes over the last few years.

Change-Id: Iea236a6ad09bc8bae9f6df8d63780bbfd4fa5619
Reviewed-on: https://review.haiku-os.org/c/haiku/+/2135
Reviewed-by: waddlesplash <waddlesplash@gmail.com>

include strings.h where appriopriate...

instead or additionally to string.h, in preparation for functions move.
* moves str[n]casecmp() functions and others to strings.h.
* strings.h doesn't include string.h anymore.
* this solves #10949

* ServerApp now maintains a mask of workspaces with temporary mode settings,
and reverts the modes if the app goes away (ie. if it crashes).
* Desktop::SetScreenMode() also set the mode on the current screen, even if
it should have been set on another screen.
* Cleaned up the Desktop.h header.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@32564 a95241bf-73f2-0310-859d-f6bbb57e9c96

* Fixed typo that prevented the app_server from restoring the
ScreenConfigurations correctly.
* Removed scoring for the screen ID alone - if there is a monitor info, we don't
want to match an existing info if it only has an ID, as that one hasn't been
stored for the current monitor.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@32556 a95241bf-73f2-0310-859d-f6bbb57e9c96

Fix gcc4 build.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@32548 a95241bf-73f2-0310-859d-f6bbb57e9c96

* Rewrote screen configuration management: VirtualScreen doesn't have anything
to do with the configurations now, instead, there is a separated
ScreenConfigurations class that maintains all known screen_configurations
per workspace (and the Workspace::Private class has two of them, one for the
current modes, one for the stored modes).
* Added Desktop::{Get|Set}ScreenMode() methods, ServerApp now only calls those.
* Getting and setting of anything else than the current screen is now supported.
* This change also fixes that a temporarily set screen mode was not being
restored on workspace switch.
* Also, the Deskbar now seems to have the wrong location a lot, which is
something that should be easily fixable therefore. I will look into this next.
* Got rid of the unhandy screen_id structure server side, and in BPrivateScreen;
we now just use an int32 - the next API break should definitely replace the
screen_id with a simple typedef.
* Some cleanup.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@32541 a95241bf-73f2-0310-859d-f6bbb57e9c96

include strings.h where appriopriate...

instead or additionally to string.h, in preparation for functions move.
* moves str[n]casecmp() functions and others to strings.h.
* strings.h doesn't include string.h anymore.
* this solves #10949

* ServerApp now maintains a mask of workspaces with temporary mode settings,
and reverts the modes if the app goes away (ie. if it crashes).
* Desktop::SetScreenMode() also set the mode on the current screen, even if
it should have been set on another screen.
* Cleaned up the Desktop.h header.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@32564 a95241bf-73f2-0310-859d-f6bbb57e9c96

* Fixed typo that prevented the app_server from restoring the
ScreenConfigurations correctly.
* Removed scoring for the screen ID alone - if there is a monitor info, we don't
want to match an existing info if it only has an ID, as that one hasn't been
stored for the current monitor.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@32556 a95241bf-73f2-0310-859d-f6bbb57e9c96

Fix gcc4 build.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@32548 a95241bf-73f2-0310-859d-f6bbb57e9c96

* Rewrote screen configuration management: VirtualScreen doesn't have anything
to do with the configurations now, instead, there is a separated
ScreenConfigurations class that maintains all known screen_configurations
per workspace (and the Workspace::Private class has two of them, one for the
current modes, one for the stored modes).
* Added Desktop::{Get|Set}ScreenMode() methods, ServerApp now only calls those.
* Getting and setting of anything else than the current screen is now supported.
* This change also fixes that a temporarily set screen mode was not being
restored on workspace switch.
* Also, the Deskbar now seems to have the wrong location a lot, which is
something that should be easily fixable therefore. I will look into this next.
* Got rid of the unhandy screen_id structure server side, and in BPrivateScreen;
we now just use an int32 - the next API break should definitely replace the
screen_id with a simple typedef.
* Some cleanup.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@32541 a95241bf-73f2-0310-859d-f6bbb57e9c96