[cctest] Move most heap related tests to test/cctest/heap and clean wrt IWYU

test/cctest/heap/test-incremental-marking.cc

Index: test/cctest/heap/test-incremental-marking.cc
diff --git a/test/cctest/test-incremental-marking.cc b/test/cctest/heap/test-incremental-marking.cc
similarity index 99%
rename from test/cctest/test-incremental-marking.cc
rename to test/cctest/heap/test-incremental-marking.cc
index ef3bad68ae3ed0e4a9a98aa17f417036d0cc83f7..6591e8445c0a4ed46b6849c22dc8e951e4a730c3 100644
--- a/test/cctest/test-incremental-marking.cc
+++ b/test/cctest/heap/test-incremental-marking.cc
@@ -22,6 +22,8 @@
 #include "src/full-codegen/full-codegen.h"
 #include "src/global-handles.h"
 #include "test/cctest/cctest.h"
+#include "test/cctest/heap/utils-inl.h"
+
 
 using v8::IdleTask;
 using v8::Task;