Fix 'eval' in class extends clauses to be always-strict

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 324d7b99b8ee807bcee65666c1ee288b6a2a9f6a..bcde21a958527b23e5c08f95454b66231d018e7d 100644
--- a/src/interpreter/bytecode-generator.cc
+++ b/src/interpreter/bytecode-generator.cc
@@ -3279,7 +3279,7 @@ void BytecodeGenerator::VisitInScope(Statement* stmt, Scope* scope) {
 
 
 LanguageMode BytecodeGenerator::language_mode() const {
-  return info()->language_mode();
+  return execution_context()->scope()->language_mode();
 }