qmake: Generated Visual Studio project defaults "GenerateDebugInformation" to "false"

It seems when generating vcxproj with CONFIG += debug_and_release, the generated project will always have "GenerateDebugInformation" set to "false" even for the Debug configuration.

Steps to reproduce:
1. Create a .pro file with following content:

    TARGET = test
    TEMPLATE = lib
    CONFIG += debug_and_release

2. Generate vcxproj using following command:

qmake.exe -tp vc test.pro -o test.vcxproj

Inspect the output test.vcxproj for <GenerateDebugInformation> xml tag value. It will be "false" for both Release and Debug Configuration.

In our case we were using the force_debug_info (CONFIG += debug_and_release force_debug_info) and expecting to have debug information generated in Release configuration as well. That didn't work either.