This is caused by deleting Engine/Intermediate/Build for binary engine builds.
FIX: The solution is to use the launcher, click the triangle next to the engine version and select “verify” it will then re-download the missing Build folder, which contains the InputCoreTypes.generated.h among others.
I’d like to report that this issue is caused by deleting the Intermediate folder after generating the C++ project. I used 4.13.2 and created a new project, then added a C++ class and generated the VS2015 project. Then I deleted the Intermediate folder. Now re-generating the VS project does not re-generate the InputCoreTypes.generated.h