app_server: Basic scaling for window borders.

This code is quite convoluted and very much in need of refactoring,
but this solution works well enough for the time being. It does not
look quite right at higher resolutions (borders come out darker than
they do at the default resolution), but at least the borders are now
the correct size instead of a constant one.

The resize nub drawing code also hasn't yet been updated, so while
it draws the gradient over the full resize area and responds to clicks,
the "checkerboard" pattern is drawn at a fixed small size still.

Nonetheless, this is a significant improvement.

app_server: Implement B_OUTLINE_RESIZE

- Allows applications to be resized without the window contents resizing with the window frame.
- Due to the nature of out-of-tree decorators using private APIs, this will require all pre-existing decorators to be rebuilt
- Newer decorators won't work on older versions of Haiku...
- Also has some formatting with license headers.
- Fixes #2724

Change-Id: Id0b45e7bbc0b636e6dffbd396eb584bf348b5296
Reviewed-on: https://review.haiku-os.org/c/haiku/+/344
Reviewed-by: Adrien Destugues <pulkomandy@gmail.com>
Reviewed-by: Jacob Secunda <secundaja@gmail.com>

Set*UIColor, etc.

The inseparable changes necessary to support live color updating across the
system in a sane, safe, and performant manner.

BView gains:

HasSystemColors()
HasDefaultColors()
AdoptSystemColors()
AdoptParentColors()
AdoptViewColor(BView*)
SetViewUIColor(color_which, float tint)
SetHighUIColor(...
SetLowUIColor(...
ViewUIColor(float* tint)
HighUIColor(...
LowUIColor(...
DelayedInvalidate()

BWindow gains a simple helper method:
IsOffscreenWindow()

BMessage gains:

AddColor()
FindColor()
GetColor()
HasColor() * allegedly this API is deprecated, but I implemented it anyway
ReplaceColor()
SetColor()

Previous private ColorTools methods are made public and moved into GraphicsDefs:

mix_color, blend_color, disable_color

These are fully compatible with BeOS dan0 R5.1 methods and are just code cleanup
of BeOS example code under the OpenTracker license.

In addition, four new colors are created:
B_LINK_TEXT_COLOR
B_LINK_HOVER_COLOR
B_LINK_ACTIVE_COLOR
B_LINK_VISITED_COLOR

These changes are documented in their proper user documentation files.

In addition, due to a history rewrite, B_FOLLOW_LEFT_TOP has been defined and
used in lieu of B_FOLLOW_TOP | B_FOLLOW_LEFT and is included in this commit.

On the app_server side, the following has changed:

Add DelayedMessage - a system by which messages can be sent at a scheduled time,
and can also be merged according to set rules. A single thread is used to service the
message queue and multiple recipients can be set for each message.
Desktop gains the ability to add message ports to a DelayedMessage so that
said messages can target either all applications or all windows, as needed.

Desktop maintains a BMessage which is used to queue up all pending color changes
and the delayed messaging system is used to enact these changes after a short
period of time has passed. This prevents abuse and allows the system to merge
repeated set_ui_color events into one event for client applications, improving
performance drastically.

In addition, B_COLORS_UPDATED is sent to the BApplication, which forwards the message
to each BWindow. This is done to improve performance over having the app_server
independently informing each window.

Decorator changes are live now, which required some reworking.

Signed-off-by: Augustin Cavalier <waddlesplash@gmail.com>

Move Tab code into Decorator and refactor

Redo close and zoom buttons

... to draw into a cached bitmap and border for BeDecorator.

Make the box positioning closer to BeOS too.

Also rearrange methods in DefaultDecorator and TabDecorator a bit.

Convert BeDecorator to derive from TabDecorator

Also, make the close and zoom buttons update when clicked.

Create a TabDecorator class

Which contains methods common to Default Decorator and BeDecorator, aka
"tabbed" decorators.

Derive DefaultDecorator from a new TabDecorator base class.

Move Tab code into Decorator and refactor

Redo close and zoom buttons

... to draw into a cached bitmap and border for BeDecorator.

Make the box positioning closer to BeOS too.

Also rearrange methods in DefaultDecorator and TabDecorator a bit.

Convert BeDecorator to derive from TabDecorator

Also, make the close and zoom buttons update when clicked.

Create a TabDecorator class

Which contains methods common to Default Decorator and BeDecorator, aka
"tabbed" decorators.

Derive DefaultDecorator from a new TabDecorator base class.