Fix for bug http://code.google.com/p/v8/issues/detail?id=1176.

src/arm/codegen-arm.cc

 // Copyright 2010 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 5832 matching lines @@
     Variable* variable = node->expression()->AsVariableProxy()->AsVariable();
     if (property != NULL) {
       Load(property->obj());
       Load(property->key());
       frame_->EmitPush(Operand(Smi::FromInt(strict_mode_flag())));
       frame_->InvokeBuiltin(Builtins::DELETE, CALL_JS, 3);
       frame_->EmitPush(r0);
 
     } else if (variable != NULL) {
       // Delete of an unqualified identifier is disallowed in strict mode
-      // so this code can only be reached in non-strict mode.
-      ASSERT(strict_mode_flag() == kNonStrictMode);
+      // but "delete this" is.
+      ASSERT(strict_mode_flag() == kNonStrictMode || variable->is_this());
       Slot* slot = variable->AsSlot();
       if (variable->is_global()) {
         LoadGlobal();
         frame_->EmitPush(Operand(variable->name()));
         frame_->EmitPush(Operand(Smi::FromInt(kNonStrictMode)));
         frame_->InvokeBuiltin(Builtins::DELETE, CALL_JS, 3);
         frame_->EmitPush(r0);
 
       } else if (slot != NULL && slot->type() == Slot::LOOKUP) {
         // Delete from the context holding the named variable.
@@ skipping 1510 matching lines @@
                BinaryOpIC::GetName(runtime_operands_type_));
   return name_;
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_ARM