[wasm] Provide better stack traces for asm.js code

src/isolate.cc

 // Copyright 2012 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/isolate.h"
 
 #include <stdlib.h>
 
 #include <fstream>  // NOLINT(readability/streams)
 #include <sstream>
@@ skipping 502 matching lines @@
         Code* code = wasm_frame->unchecked_code();
         Handle<AbstractCode> abstract_code(AbstractCode::cast(code), this);
         const int offset =
             static_cast<int>(wasm_frame->pc() - code->instruction_start());
 
         // TODO(wasm): The wasm object returned by the WasmFrame should always
         //             be a wasm object.
         DCHECK(wasm::IsWasmObject(*wasm_object) ||
                wasm_object->IsUndefined(this));
 
-        elements = FrameArray::AppendWasmFrame(
-            elements, wasm_object, wasm_function_index, abstract_code, offset,
-            FrameArray::kIsWasmFrame);
+        int flags = wasm::WasmIsAsmJs(*wasm_object, this)
+                        ? FrameArray::kIsAsmJsWasmFrame
+                        : FrameArray::kIsWasmFrame;
+
+        elements = FrameArray::AppendWasmFrame(elements, wasm_object,
+                                               wasm_function_index,
+                                               abstract_code, offset, flags);
       } break;
 
       default:
         break;
     }
   }
 
   elements->ShrinkToFit();
 
   // TODO(yangguo): Queue this structured stack trace for preprocessing on GC.
@@ skipping 2841 matching lines @@
   // Then check whether this scope intercepts.
   if ((flag & intercept_mask_)) {
     intercepted_flags_ |= flag;
     return true;
   }
   return false;
 }
 
 }  // namespace internal
 }  // namespace v8