Add a GetDisplayName() API to SBFrame, SBFunction and SBSymbol

This API is currently a no-op (in the sense that it has the same behavior as the already existing GetName()), but is meant long-term to provide a best-for-visualization version of the name of a function

It is still not hooked up to the command line 'bt' command, nor to the 'gui' mode, but I do have ideas on how to make that work going forward

rdar://21203242

llvm-svn: 241482
diff --git a/lldb/source/Core/Mangled.cpp b/lldb/source/Core/Mangled.cpp
index 3e1a8bb..0947106 100644
--- a/lldb/source/Core/Mangled.cpp
+++ b/lldb/source/Core/Mangled.cpp
@@ -339,6 +339,12 @@
 }
 
 
+ConstString
+Mangled::GetDisplayDemangledName () const
+{
+    return GetDemangledName();
+}
+
 bool
 Mangled::NameMatches (const RegularExpression& regex) const
 {