[interpreter] Add explicit OSR polling bytecode.

src/interpreter/interpreter-assembler.h

Index: src/interpreter/interpreter-assembler.h
diff --git a/src/interpreter/interpreter-assembler.h b/src/interpreter/interpreter-assembler.h
index 8c15488db7f67d6411cbf8617d909444468c7ad4..e21a02c837494b21f98c693b1ac28e79e8583ddb 100644
--- a/src/interpreter/interpreter-assembler.h
+++ b/src/interpreter/interpreter-assembler.h
@@ -145,6 +145,9 @@ class InterpreterAssembler : public CodeStubAssembler {
   // Updates the profiler interrupt budget for a return.
   void UpdateInterruptBudgetOnReturn();
 
+  // Returns the OSR nesting level from the bytecode header.
+  compiler::Node* LoadOSRNestingLevel();
+
   // Dispatch to the bytecode.
   compiler::Node* Dispatch();