More avoidance of invoking gdb with LD_LIBRARY_PATH set

...similar to 785eb0ed "gbuild: try to avoid
invoking gdb with LD_LIBRARY_PATH set", this time for DEBUGCPPUNIT=TRUE in
addition to CPPUNITTRACE="gdb --args"

Change-Id: I3e2cc5abf76947dc4c7b4d6caa3fd5720720e050

solenv/gbuild/CppunitTest.mk

@@ -123,7 +123,7 @@ else
 		( \
 		$(if $(gb_CppunitTest_localized),for l in $(WITH_LANG_LIST) ; do LO_TEST_LOCALE="$$l" ) \
 		$(if $(gb_CppunitTest_PREGDBTRACE),$(gb_CppunitTest_PREGDBTRACE) &&) \
-		$(if $(filter gdb,$(CPPUNITTRACE)),,$(gb_CppunitTest_CPPTESTPRECOMMAND)) \
+		$(if $(filter gdb,$(gb_CppunitTest_GDBTRACE)),,$(gb_CppunitTest_CPPTESTPRECOMMAND)) \
 		$(if $(G_SLICE),G_SLICE=$(G_SLICE)) \
 		$(if $(GLIBCXX_FORCE_NEW),GLIBCXX_FORCE_NEW=$(GLIBCXX_FORCE_NEW)) \
 		$(gb_CppunitTest_malloc_check) \

solenv/gbuild/platform/com_GCC_class.mk

@@ -122,7 +122,7 @@ endef
 # CppunitTest class
 
 ifeq ($(strip $(DEBUGCPPUNIT)),TRUE)
-gb_CppunitTest_GDBTRACE := gdb -nx -ex "add-auto-load-safe-path $(INSTDIR)" --batch --command=$(SRCDIR)/solenv/bin/gdbtrycatchtrace-stdout -return-child-result --args
+gb_CppunitTest_GDBTRACE := gdb -nx -ex "add-auto-load-safe-path $(INSTDIR)" -ex "set environment $(subst =, ,$(gb_CppunitTest_CPPTESTPRECOMMAND))" --batch --command=$(SRCDIR)/solenv/bin/gdbtrycatchtrace-stdout -return-child-result --args
 endif
 
 # ExternalProject class