XCB: Don't recalculate the DPI if we have a forced DPI setting

logicalDpi() already has the logic to check m_forcedDpi, so let's reuse
it. I hope it's not a problem that we send a signal that it changed when
nothing changed.

[ChangeLog][Platform Specific Changes][X11 / XCB]Fixed a bug that caused
Qt applications to think the screen DPI had changed when it had not,
after connecting or disconnecting monitors.

Task-number: QTBUG-32683
Change-Id: I45dd27de5109e65e7599915f11cfdb633a65a67c
Reviewed-by: Robin Burchell <robin+qt@viroteck.net>
Reviewed-by: Shawn Rutledge <shawn.rutledge@digia.com>
xcb: added env variables to show input devices and events

export QT_XCB_DEBUG_XINPUT_DEVICES=anything to show detected
input devices at startup
export QT_XCB_DEBUG_XINPUT=anything to log mouse, touch and tablet events

Change-Id: Id14844b68ad376740f82a36aab2c59c84d2017ab
Task-number: QTBUG-35583
Reviewed-by: Jørgen Lind <jorgen.lind@digia.com>
fix compile of qt without egl available

move the dpy to the place where it is used inside the egl ifdef guard
fixes compilation on old distros not having egl

Change-Id: I7eebe5305f3a584c0c5da2ea7b9099fdd994249d
Reviewed-by: David Faure <david.faure@kdab.com>
Doc: Polish Qt::ConnectionType descriptions

- Shorten Qt::AutoConnection description, rearrange to match the order
  of the subsequent rows.
- Note the thread used in Qt::DirectConnection
- "Emitter's thread" is ambiguous -- a signal is not necessarily
  emitted from the thread that the emitter lives in.
- Misusing Qt::BlockingQueuedConnection WILL (not "can") cause a
  deadlock. Qt even issues an error message before it freezes.
- Remove the \note command -- it breaks the table and displays the note
  in a new paragraph.

Change-Id: Ib60cb665e0cd23e1e072402ec5d8be344b8454f7
Reviewed-by: Olivier Goffart <ogoffart@woboq.com>
Reviewed-by: Topi Reiniö <topi.reinio@digia.com>
Reviewed-by: Giuseppe D'Angelo <giuseppe.dangelo@kdab.com>
Add mtdev configure test

Change-Id: If989b479ed4babf902099c54be59ae73512820d5
Reviewed-by: Laszlo Agocs <laszlo.agocs@digia.com>
linuxfb: Make mouse cursor behavior match eglfs

On non-Android systems hideCursor should default to false, just
like it is done in eglfs. This is especially useful on udev-less
systems where currently one has to resort to setting
QT_QPA_FB_HIDECURSOR to "0" to enable the mouse cursor. This is
not ideal. Defaulting to showing the cursor unless disabled by
the environment variable or, in absence of that, the lack of a
mouse reported by udev is a better choice.

Change-Id: I7362ac47046179d5eb8ed8b44cf2c36c0fc23432
Reviewed-by: Jørgen Lind <jorgen.lind@digia.com>
mtdev: Change to use configure detection instead of requiring source hacking.

This coincidentally fixes a case of accidental BIC in qevdevtouch_p.h, where not
all users would necessarily define USE_MTDEV: having it centralized inside Qt
makes this now, blessedly, impossible.

Change-Id: I196a8f21742830705759aa917a823afdc94ba2b5
Done-with: Michael Brasser <michael.brasser@jollamobile.com>
Reviewed-by: Laszlo Agocs <laszlo.agocs@digia.com>
Windows platform plugin: Add missing case statement

Change-Id: I9b9fc6cf000b262277711374e0a2fe119328849e
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@digia.com>
Reviewed-by: Konstantin Ritt <ritt.ks@gmail.com>
Improve QFileSelector doc

Mostly just adding proper tags and sections, as well as a few
grammatical fixes.

Change-Id: I219517d740fa7385e923a9e09cb7e241378fcbdd
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
Reviewed-by: Martin Smith <martin.smith@digia.com>