HotSpot uses precompiled headers to speed up non-incremental builds. The current mechanism requires all .cpp files to include precompiled.hpp as the first non-comment line. This requires HotSpot devs to think about precompiled headers when they create new files and when they need to update/manage the include sections.

All the compilers that we use support inclusions of the precompiled.hpp from the command line instead. I propose that we use that mechanism instead.