[wasm] Implement stepping in wasm code

src/frames.cc

Index: src/frames.cc
diff --git a/src/frames.cc b/src/frames.cc
index c1ef5ee131707e75f759c5dc61fc70a23b8b316a..1840f935def69df7331f1670e9be555d79f5d6b0 100644
--- a/src/frames.cc
+++ b/src/frames.cc
@@ -131,16 +131,6 @@ StackFrame* StackFrameIteratorBase::SingletonFor(StackFrame::Type type) {
 
 // -------------------------------------------------------------------------
 
-JavaScriptFrameIterator::JavaScriptFrameIterator(Isolate* isolate,
-                                                 StackFrame::Id id)
-    : iterator_(isolate) {
-  while (!done()) {
-    Advance();
-    if (frame()->id() == id) return;
-  }
-}
-
-
 void JavaScriptFrameIterator::Advance() {
   do {
     iterator_.Advance();