Compiling compiler-rt with Clang modules and libc++ revealed that the
global `operator new` is being called without including `<new>`.
Differential Revision: https://reviews.llvm.org/D105401
While the VMO size is always page aligned, we can record the content
size as a property and then use this metadata when writing the data to
a file.
Differential Revision: https://reviews.llvm.org/D76462