[wasm] Implement stepping in wasm code

src/frames.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/frames.h"
 
 #include <memory>
 #include <sstream>
 
 #include "src/base/bits.h"
@@ skipping 113 matching lines @@
     STACK_FRAME_TYPE_LIST(FRAME_TYPE_CASE)
     default: break;
   }
   return NULL;
 
 #undef FRAME_TYPE_CASE
 }
 
 // -------------------------------------------------------------------------
 
-JavaScriptFrameIterator::JavaScriptFrameIterator(Isolate* isolate,
-                                                 StackFrame::Id id)
-    : iterator_(isolate) {
-  while (!done()) {
-    Advance();
-    if (frame()->id() == id) return;
-  }
-}
-
-
 void JavaScriptFrameIterator::Advance() {
   do {
     iterator_.Advance();
   } while (!iterator_.done() && !iterator_.frame()->is_java_script());
 }
 
 
 void JavaScriptFrameIterator::AdvanceToArgumentsFrame() {
   if (!frame()->has_adapted_arguments()) return;
   iterator_.Advance();
@@ skipping 2083 matching lines @@
   for (StackFrameIterator it(isolate); !it.done(); it.Advance()) {
     StackFrame* frame = AllocateFrameCopy(it.frame(), zone);
     list.Add(frame, zone);
   }
   return list.ToVector();
 }
 
 
 }  // namespace internal
 }  // namespace v8