[C++] Don't put model includes on -isystem path in test

Summary:
It's not necessary if compiling tests in infer environemnt. It may be required if compiling some C++ tests
without infer. `infer/tests/codetoanalyze/cpp/shared/attributes/depracated_hack.cpp` is one of them

Reviewed By: cristianoc

Differential Revision: D4008850

fbshipit-source-id: 5d94bdf

infer/tests/codetoanalyze/cpp/errors/Makefile

@@ -7,7 +7,7 @@
 
 include ../../Makefile.clang
 
-OPTIONS = -x c++ -std=c++11 -isystem$(MODELS_DIR)/cpp/include -isystem$(CLANG_INCLUDES)/c++/v1/ -c
+OPTIONS = -x c++ -std=c++11 -isystem$(ROOT_DIR) -isystem$(CLANG_INCLUDES)/c++/v1/ -c
 
 FILES = \
   c_tests/*.cpp \

infer/tests/codetoanalyze/cpp/frontend/Makefile

@@ -7,7 +7,7 @@
 
 include ../../Makefile.frontend
 
-OPTIONS = -x c++ -std=c++11 -isystem$(MODELS_DIR)/cpp/include -isystem$(CLANG_INCLUDES)/c++/v1/ -c
+OPTIONS = -x c++ -std=c++11 -isystem$(ROOT_DIR) -isystem$(CLANG_INCLUDES)/c++/v1/ -c
 
 FILES = \
   */*.cpp shared/*/*.cpp \

infer/tests/codetoanalyze/cpp/shared/attributes/deprecated_hack.cpp

@@ -9,9 +9,9 @@
 
 // header required by TranslateAsPtr class. It's not in common header search
 // path when running clang without infer (clang wrappers add it)
-// Add -isystem '/path/models/cpp/include' to clang invocation to work around
+// Add -isystem '/path/to/infer/repo' to clang invocation to work around
 // compilation problem
-#include <infer_model/infer_traits.h>
+#include <infer/models/cpp/include/infer_model/infer_traits.h>
 
 /* Test for passing function attributes to infer via __deprecated__ attribute */