Engine test suite fails to build

[max]

When you build XCSoar right before building the engine test suite, the build fails:

LINK output/UNIX/bin/test_replay

/usr/bin/ld: output/UNIX/harness.a(test_debug.o): in function distance_counts():test/src/test_debug.cpp:40: error: undefined reference to 'count_distbearing'
/usr/bin/ld: output/UNIX/harness.a(test_debug.o): in function distance_counts():test/src/test_debug.cpp:41: error: undefined reference to 'count_mc'
/usr/bin/ld: output/UNIX/harness.a(test_debug.o): in function distance_counts():test/src/test_debug.cpp:42: error: undefined reference to 'n_queries'
/usr/bin/ld: output/UNIX/harness.a(test_debug.o): in function distance_counts():test/src/test_debug.cpp:43: error: undefined reference to 'n_queries'
/usr/bin/ld: output/UNIX/harness.a(test_debug.o): in function distance_counts():test/src/test_debug.cpp:44: error: undefined reference to 'n_queries'
/usr/bin/ld: output/UNIX/harness.a(test_debug.o): in function distance_counts():test/src/test_debug.cpp:61: error: undefined reference to 'n_queries'
/usr/bin/ld: output/UNIX/harness.a(test_debug.o): in function distance_counts():test/src/test_debug.cpp:62: error: undefined reference to 'count_distbearing'
/usr/bin/ld: output/UNIX/harness.a(test_debug.o): in function distance_counts():test/src/test_debug.cpp:63: error: undefined reference to 'count_mc'
collect2: ld returned 1 exit status
make: *** [output/UNIX/bin/test_replay] Error 1

[max]

This happens because the "test engine" is not ABI compatible with the "real engine" (built with different CPP parameters). Decreasing priority, but we should eventually do this properly.

[jwharington]

retain globals now so ABI compatible.