Simplify pushing function argument for context allocation.

src/full-codegen.h

Index: src/full-codegen.h
diff --git a/src/full-codegen.h b/src/full-codegen.h
index 6958daeb8d58df42d0eaf6060aa3f0ee30249b68..9f7e4477c6ec7ed5508d6256cb5235ce79d6b14a 100644
--- a/src/full-codegen.h
+++ b/src/full-codegen.h
@@ -595,9 +595,9 @@ class FullCodeGenerator: public AstVisitor {
   // in v8::internal::Context.
   void LoadContextField(Register dst, int context_index);
 
-  // Push the function argument for the runtime functions PushWithContext
-  // and PushCatchContext.
-  void PushFunctionArgumentForContextAllocation();
+  // Push the function argument for the runtime functions PushWithContext,
+  // PushCatchContext and PushBlockContext.
+  void PushFunctionArgumentForContextAllocation(Register scratch);
 
   // AST node visit functions.
 #define DECLARE_VISIT(type) virtual void Visit##type(type* node);