Found with -Wdouble-promotion
Signed-off-by: Rosen Penev <rosenp@gmail.com>

It's available there.
Signed-off-by: Rosen Penev <rosenp@gmail.com>

Found with -Wdouble-promotion
Signed-off-by: Rosen Penev <rosenp@gmail.com>

Boost does not seem to offer an overload for lrint.
Signed-off-by: Rosen Penev <rosenp@gmail.com>

The former was deprecated with C++14.

According to the C++11 and C++17 standards, both files are identical.
Signed-off-by: Rosen Penev <rosenp@gmail.com>

Since we switched from autotools to Meson in commit
94592c14, we don't need to include
`config.h` early to properly enable large file support.  Meson passes
the required macros on the compiler command line instead of defining
them in `config.h`.

This means we can include `config.h` at any time, whenever we want to
check its macros, and there are no ordering constraints.

Yet another global variable removed.

Move code from ReplayGainConfig.cxx.

Move code from replay_gain_get_real_mode().

Prepare for moving idle events to class Partition.  Right now, it's
just a wrapper for idle_add().

Migrate the remaining callers to FatalError().

Use only ConfigData.hxx in plugin sources to reduce header
dependencies.