Test support for OLD behavior of policy CMP0002

Policy CMP0002's OLD behavior allows duplicate non-custom targets.  We
test it with a project that builds two executables of the same name by
setting CMP0002 to OLD.

Tests/CMakeLists.txt

@@ -124,6 +124,9 @@ IF(BUILD_TESTING)
   ADD_TEST_MACRO(ExportImport ExportImport)
   ADD_TEST_MACRO(Unset Unset)
   ADD_TEST_MACRO(PolicyScope PolicyScope)
+  IF("${CMAKE_TEST_GENERATOR}" MATCHES "Make")
+    ADD_TEST_MACRO(Policy0002 Policy0002)
+  ENDIF("${CMAKE_TEST_GENERATOR}" MATCHES "Make")
 
   SET(CMAKE_BUILD_TEST_SOURCE_DIR "${CMake_SOURCE_DIR}/Tests/COnly")
   SET(CMAKE_BUILD_TEST_BINARY_DIR "${CMake_BINARY_DIR}/Tests/CMakeBuildCOnly")

Tests/Policy0002/A/CMakeLists.txt

@@ -0,0 +1 @@
+add_executable(Policy0002 ../policy0002.c)

Tests/Policy0002/CMakeLists.txt

@@ -0,0 +1,5 @@
+cmake_minimum_required(VERSION 2.6)
+project(Policy0002 C)
+cmake_policy(SET CMP0002 OLD)
+add_subdirectory(A)
+add_executable(Policy0002 policy0002.c)

Tests/Policy0002/policy0002.c

@@ -0,0 +1,4 @@
+int main(void)
+{
+  return 0;
+}