Add WasmFrame, backtraces reflect wasm's presence

src/frames.cc

Index: src/frames.cc
diff --git a/src/frames.cc b/src/frames.cc
index 50a2e21a055d7a9d8f11442f6cfa024d555c71dc..173b67c355097281ffb9ef34dea513f0649168b8 100644
--- a/src/frames.cc
+++ b/src/frames.cc
@@ -137,10 +137,17 @@ StackFrame* StackFrameIteratorBase::SingletonFor(StackFrame::Type type) {
 
 // -------------------------------------------------------------------------
 
+void VisibleFrameIterator::Advance() {
+  do {
+    iterator_.Advance();
+  } while (!iterator_.done() && !iterator_.frame()->is_visible());
+}
+
+// -------------------------------------------------------------------------
 
-JavaScriptFrameIterator::JavaScriptFrameIterator(
-    Isolate* isolate, StackFrame::Id id)
-    : iterator_(isolate) {
+JavaScriptFrameIterator::JavaScriptFrameIterator(Isolate* isolate,
+                                                 StackFrame::Id id)
+    : VisibleFrameIterator(isolate) {
   while (!done()) {
     Advance();
     if (frame()->id() == id) return;
@@ -446,7 +453,7 @@ StackFrame::Type StackFrame::ComputeType(const StackFrameIteratorBase* iterator,
       case Code::OPTIMIZED_FUNCTION:
         return OPTIMIZED;
       case Code::WASM_FUNCTION:
-        return STUB;
+        return WASM;
       case Code::BUILTIN:
         if (!marker->IsSmi()) {
           if (StandardFrame::IsArgumentsAdaptorFrame(state->fp)) {
@@ -1222,6 +1229,32 @@ void StackFrame::PrintIndex(StringStream* accumulator,
   accumulator->Add((mode == OVERVIEW) ? "%5d: " : "[%d]: ", index);
 }
 
+void WasmFrame::Print(StringStream* accumulator, PrintMode mode,
+                      int index) const {}
+
+Code* WasmFrame::unchecked_code() const {
+  return static_cast<Code*>(isolate()->FindCodeObject(pc()));
+}
+
+void WasmFrame::Iterate(ObjectVisitor* v) const { IterateCompiledFrame(v); }
+
+void WasmFrame::Summarize(List<FrameSummary>* frames) {
+  DCHECK(frames->length() == 0);
+  // TODO(jfb) Do something useful.
+  Object* object = Object::cast(*Handle<Object>::null());
+  JSFunction* jsfunction = JSFunction::cast(*Handle<JSFunction>::null());
+  Code* code = LookupCode();
+  DCHECK(code->is_wasm_code());
+  unsigned code_offset = 0;
+  bool is_constructor = false;
+  FrameSummary summary(object, jsfunction, AbstractCode::cast(code),
+                       code_offset, is_constructor);
+  frames->Add(summary);
+}
+
+Address WasmFrame::GetCallerStackPointer() const {
+  return fp() + ExitFrameConstants::kCallerSPDisplacement;
+}
 
 namespace {