[interpreter, debugger] support debug breaks via bytecode array copy

src/interpreter/bytecode-generator.cc

Index: src/interpreter/bytecode-generator.cc
diff --git a/src/interpreter/bytecode-generator.cc b/src/interpreter/bytecode-generator.cc
index c0f5750351784b62d0f57247e94e22bc076487b7..3aad14b067f68443c64dd8fa0e5912b516a4e2ed 100644
--- a/src/interpreter/bytecode-generator.cc
+++ b/src/interpreter/bytecode-generator.cc
@@ -898,7 +898,7 @@ void BytecodeGenerator::VisitBreakStatement(BreakStatement* stmt) {
 
 void BytecodeGenerator::VisitReturnStatement(ReturnStatement* stmt) {
   VisitForAccumulatorValue(stmt->expression());
-  builder()->SetReturnPosition(info_->literal());
+  builder()->SetStatementPosition(stmt);

[Yang, 2016/02/16 09:22:20]

Turns out I've been wrong about setting the return position here before. This
here matches what FCG does.

[rmcilroy, 2016/02/16 10:46:38]

Ack. Note: we will only get a SetReturnPosition now where there is an implicit
return - just making sure this is what we want.

Should we make SetReturnPosition private to ensure we only set it on implicit
returns?

[Yang, 2016/02/19 13:09:17]

Done.

   execution_control()->ReturnAccumulator();
 }