[generators] Add asserts preventing mixed functions.

src/objects.cc

 // Copyright 2015 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/objects.h"
 
 #include <cmath>
 #include <iomanip>
 #include <memory>
 #include <sstream>
@@ skipping 19150 matching lines @@
         isolate, DependentCode::kPropertyCellChangedGroup);
   }
 }
 
 int JSGeneratorObject::source_position() const {
   CHECK(is_suspended());
   AbstractCode* code;
   int code_offset;
   if (function()->shared()->HasBytecodeArray()) {
     // New-style generators.
+    DCHECK(!function()->shared()->HasBaselineCode());
     code_offset = Smi::cast(input_or_debug_pos())->value();
     // The stored bytecode offset is relative to a different base than what
     // is used in the source position table, hence the subtraction.
     code_offset -= BytecodeArray::kHeaderSize - kHeapObjectTag;
     code = AbstractCode::cast(function()->shared()->bytecode_array());
   } else {
     // Old-style generators.
+    DCHECK(function()->shared()->HasBaselineCode());
     code_offset = continuation();
     CHECK(0 <= code_offset);
     CHECK(code_offset < function()->code()->instruction_size());
     code = AbstractCode::cast(function()->shared()->code());
   }
   return code->SourcePosition(code_offset);
 }
 
 // static
 AccessCheckInfo* AccessCheckInfo::Get(Isolate* isolate,
@@ skipping 18 matching lines @@
   for (PrototypeIterator iter(isolate, this, kStartAtReceiver,
                               PrototypeIterator::END_AT_NULL);
        !iter.IsAtEnd(); iter.AdvanceIgnoringProxies()) {
     if (iter.GetCurrent<Object>()->IsJSProxy()) return true;
   }
   return false;
 }
 
 }  // namespace internal
 }  // namespace v8