Qt WebEngine Automagic Linking to Qt Positioning

When building with 'webengine-geolocation' enabled, and no Qt Positioning installed, configure correctly bails, but when building with 'webengine-geolocation' disabled, and Qt Positioning installed:

libQt5WebEngine.so => /usr/lib64/libQt5WebEngine.so (interpreter => none)
    libQt5WebEngineCore.so.5 => /usr/lib64/libQt5WebEngineCore.so.5
        libQt5Positioning.so.5 => /usr/lib64/libQt5Positioning.so.5

Moreover, if Qt WebEngine is first built with geolocation support, then Qt Positioning is removed, and WebEngine is rebuilt without geolocation, the build fails:

/usr/lib/gcc/x86_64-pc-linux-gnu/9.2.0/../../../../x86_64-pc-linux-gnu/bin/ld: /[...]/src/core/release/obj/QtWebEngineCore/content_browser_client_qt.o: in function `QtWebEngineCore::ContentBrowserClientQt::OverrideSystemLocationProvider()':
/[...]/src/core/content_browser_client_qt.cpp:691: undefined reference to `QtWebEngineCore::LocationProviderQt::LocationProviderQt()'
collect2: error: ld returned 1 exit status

Uninstalling the previous build before rebuilding allows for things to continue on again.

The latter part may well be something outside of what Qt can help with, but perhaps there is at least something that can be done about the automagic linking here?

I'm not entirely sure when this started happening, but going through Gentoo bugs it seems it was around 5.11 and 5.12.