On macOS context menu (right click) doesn't activate the window that was clicked.
- You can't activate it yourself if some other application is active.
- It's hard to make menu work while window still is inactive (like macOS menus).
Because when you left-click anything after right click Qt makes the window
something-like-focused (it shows on top and receives input), but not really
(it still displays as inactive, cursor not blinking and all). Looks like Qt bug.
base::lambda -> Fn (type alias for std::function).
base::lambda_once -> FnMut (type alias for base::unique_function).
base::lambda_guarded -> crl::guard.
base::lambda_call_type_t -> crl::deduced_call_type.
Also don't change mask corner images when color theme is changed.
This prevents race condition in mask corner images access, because
the GIF frame readers access mask corner images from other threads.
Use Qt::Dialog instead of Qt::Tool which works better with window
activation / deactivation handling.
Stop displaying the panel on all spaces when the call is established.
Currently the build without implicitly included precompiled header
is not supported anyway (because Qt MOC source files do not include
stdafx.h, they include plain headers).
So when we decide to support building without implicitly included
precompiled headers we'll have to fix all the headers anyway.
Now base::lambda can be copied and can wrap any immutable lambda.
For mutable lambdas there is base::lambda_once (which you're
supposed to call only once to pass data through lambda captures,
for example by using std::unique_ptr). Generally base::lambda is
passed by value and base::lambda_once is passed by rvalue reference.
