src, tests: fix -Wint-to-pointer-cast and a chance of test crashpersonal/peat-psuwit/protected-superclass

Turns the constructor of `VolumeControl` and `VolumeWarning` from
`internal` to `protected`. This makes Vala emits C declaration of
constructors, which is required by the test's mocks extending these
classes, in the external header.

Without them, the mocks' C code would then consider them "implicitly
declared", and will assume they return `int` instead of a pointer. If
the returned address happened to be higher than `INT_MAX`, the code will
consider the returned address negative and sign-extend it when casting
to a pointer, corrupting it.

As for "unprivating" these constructors, this is an internal static
library anyway. No libraries or headers are installed from this package.
This change is invisible from outside.

0 files changed, 0 insertions, 0 deletions