First stab at try-catch and try-finally in TurboFan.

src/compiler/graph-builder.h

Index: src/compiler/graph-builder.h
diff --git a/src/compiler/graph-builder.h b/src/compiler/graph-builder.h
index 8374675ab62f9ea5b842a87a3cf4e301cad95d8b..57628990b2b7f8eba6db89697fbf9bd35a6c5161 100644
--- a/src/compiler/graph-builder.h
+++ b/src/compiler/graph-builder.h
@@ -235,6 +235,12 @@ class StructuredGraphBuilder::Environment : public ZoneObject {
   CommonOperatorBuilder* common() { return builder_->common(); }
   NodeVector* values() { return &values_; }
 
+  // Friends using the values vector.
+  // TODO(mstarzinger): Un-friend once AstGraphBuilder has been merged with
+  // StructuredGraphBuilder.
+  friend class TryCatchBuilder;
+  friend class TryFinallyBuilder;
+
   // Prepare environment to be used as loop header.
   void PrepareForLoop(BitVector* assigned, bool is_osr = false);