Revert "I had recently added a new SBFrame::GetVariables() overload with yet another bool argument"

This reverts commit r228975.  It was causing link errors
on the Windows bots, since last Thursday.

http://lab.llvm.org:8011/builders/lldb-x86-win7-msvc/builds/725

Conflicts:
	lldb.xcodeproj/project.pbxproj

llvm-svn: 229514