Revert r268591

"Allow LanguageRuntimes to return an error if they fail in the course of dynamic type discovery

This is not meant to report that a value doesn't have a dynamic type - it is only meant as a mechanism to propagate actual type discovery issues (e.g. malformed type metadata for languages that have such a notion)

This information is used by ValueObjectDynamic to set its own m_error, which is a fairly sharp and heavyweight tool to begin with

For the time being, this is an architectural improvement but a practical no-op as no existing runtimes are actually setting errors"

I need to think about what I want to do in this space more carefully - this attempt might be too heavy of a hammer for the nail I am trying to fix, and I don't want to leave it in while I ponder

llvm-svn: 268686