[generators] Implement %GeneratorGetSourcePosition.

src/parsing/parser.cc

Index: src/parsing/parser.cc
diff --git a/src/parsing/parser.cc b/src/parsing/parser.cc
index 65466559b4be24c52049e3f05e4dea9a10bbe4db..574472d2464ed646a752f194bfd8834ff3cbd314 100644
--- a/src/parsing/parser.cc
+++ b/src/parsing/parser.cc
@@ -680,13 +680,14 @@ Expression* ParserTraits::NewTargetExpression(Scope* scope,
 Expression* ParserTraits::FunctionSentExpression(Scope* scope,
                                                  AstNodeFactory* factory,
                                                  int pos) {
-  // We desugar function.sent into %_GeneratorGetInput(generator).
+  // We desugar function.sent into %_GeneratorGetInputOrDebugPos(generator).
   Zone* zone = parser_->zone();
   ZoneList<Expression*>* args = new (zone) ZoneList<Expression*>(1, zone);
   VariableProxy* generator = factory->NewVariableProxy(
       parser_->function_state_->generator_object_variable());
   args->Add(generator, zone);
-  return factory->NewCallRuntime(Runtime::kInlineGeneratorGetInput, args, pos);
+  return factory->NewCallRuntime(Runtime::kInlineGeneratorGetInputOrDebugPos,
+                                 args, pos);
 }