[debugger] fix break locations for assignments and return.

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 0af549ca266c36216362c248b7d63ae9cf2bff40..ae4404a035e570e176c535191472179696822acf 100644
--- a/src/interpreter/bytecode-generator.cc
+++ b/src/interpreter/bytecode-generator.cc
@@ -573,6 +573,8 @@ Handle<BytecodeArray> BytecodeGenerator::MakeBytecode(CompilationInfo* info) {
       isolate(), zone(), info->num_parameters_including_this(),
       scope()->MaxNestedContextChainLength(), scope()->num_stack_slots()));
 
+  builder()->InitializeReturnPosition(info->literal());
+
   // Initialize the incoming context.
   ContextScope incoming_context(this, scope(), false);
 
@@ -877,8 +879,8 @@ void BytecodeGenerator::VisitBreakStatement(BreakStatement* stmt) {
 
 
 void BytecodeGenerator::VisitReturnStatement(ReturnStatement* stmt) {
-  VisitForAccumulatorValue(stmt->expression());
   builder()->SetStatementPosition(stmt);
+  VisitForAccumulatorValue(stmt->expression());
   execution_control()->ReturnAccumulator();
 }