wasm: implemente WasmFrame::cast, fix inheritance

src/frames.h

 // 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.
 
 #ifndef V8_FRAMES_H_
 #define V8_FRAMES_H_
 
 #include "src/allocation.h"
 #include "src/handles.h"
 #include "src/safepoint-table.h"
@@ skipping 943 matching lines @@
   // GC support.
   void Iterate(ObjectVisitor* v) const override;
 
   // Printing support.
   void Print(StringStream* accumulator, PrintMode mode,
              int index) const override;
 
   // Determine the code for the frame.
   Code* unchecked_code() const override;
 
+  static WasmFrame* cast(StackFrame* frame) {
+    DCHECK(frame->is_wasm());
+    return static_cast<WasmFrame*>(frame);
+  }
+
  protected:
   inline explicit WasmFrame(StackFrameIteratorBase* iterator);
 
   Address GetCallerStackPointer() const override;
 
  private:
   friend class StackFrameIteratorBase;
 };
 
-class WasmToJsFrame : public WasmFrame {
+class WasmToJsFrame : public StubFrame {
  public:
   Type type() const override { return WASM_TO_JS; }
 
  protected:
   inline explicit WasmToJsFrame(StackFrameIteratorBase* iterator);
 
  private:
   friend class StackFrameIteratorBase;
 };
 
-class JsToWasmFrame : public WasmFrame {
+class JsToWasmFrame : public StubFrame {
  public:
   Type type() const override { return JS_TO_WASM; }
 
  protected:
   inline explicit JsToWasmFrame(StackFrameIteratorBase* iterator);
 
  private:
   friend class StackFrameIteratorBase;
 };
 
@@ skipping 200 matching lines @@
 
 
 // Reads all frames on the current stack and copies them into the current
 // zone memory.
 Vector<StackFrame*> CreateStackMap(Isolate* isolate, Zone* zone);
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_FRAMES_H_