Add support for parsing and representing C++ constructor declarations.

Notes:
  - Constructors are never found by name lookup, so they'll never get
    pushed into any scope. Instead, they are stored as an 
    OverloadedFunctionDecl in CXXRecordDecl for easy overloading.
  - There's a new action isCurrentClassName that determines whether an
    identifier is the name of the innermost class currently being defined;
    we use this to identify the declarator-id grammar rule that refers to 
    a type-name. 
  - MinimalAction does *not* support parsing constructors.
  - We now handle virtual and explicit function specifiers.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@58499 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Parse/MinimalAction.cpp b/lib/Parse/MinimalAction.cpp
index c98830c..2fec359 100644
--- a/lib/Parse/MinimalAction.cpp
+++ b/lib/Parse/MinimalAction.cpp
@@ -63,6 +63,12 @@
   return 0;
 }
 
+/// isCurrentClassName - Always returns false, because MinimalAction
+/// does not support C++ classes with constructors.
+bool MinimalAction::isCurrentClassName(const IdentifierInfo &, Scope *) {
+  return false;
+}
+
 /// ActOnDeclarator - If this is a typedef declarator, we modify the
 /// IdentifierInfo::FETokenInfo field to keep track of this fact, until S is
 /// popped.