Add an additional hook to the DebuggerClient during name lookups.

Author: bgogul

include/swift/AST/DebuggerClient.h

@@ -61,6 +61,11 @@ class DebuggerClient {
                                SourceLoc Loc, bool IsTypeLookup,
                                ResultVector &RV) = 0;
 
+  /// Allows the DebuggerClient to prune the results of a name lookup before
+  /// returning to the caller. (See finishLookup in NameLookup.cpp.)
+  virtual void finishLookup(const DeclContext *dc, NLOptions options,
+                            SmallVectorImpl<ValueDecl *> &decls) {}
+
   /// When evaluating an expression in the context of an existing source file,
   /// we may want to prefer declarations from that source file.
   /// The DebuggerClient can return a private-discriminator to tell lookup to

lib/AST/NameLookup.cpp

@@ -20,6 +20,7 @@
 #include "swift/AST/ASTVisitor.h"
 #include "swift/AST/ClangModuleLoader.h"
 #include "swift/AST/DebuggerClient.h"
+#include "swift/AST/DeclContext.h"
 #include "swift/AST/ExistentialLayout.h"
 #include "swift/AST/LazyResolver.h"
 #include "swift/AST/Initializer.h"