[WASM] Implements catch for the wasm low level exception mechanism.

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 1038 matching lines @@
  public:
   Type type() const override { return WASM; }
 
   // GC support.
   void Iterate(ObjectVisitor* v) const override;
 
   // Printing support.
   void Print(StringStream* accumulator, PrintMode mode,
              int index) const override;
 
+  // Lookup exception handler for current {pc}, returns -1 if none found. Also
+  // returns the stack slot count of the entire frame.
+  int LookupExceptionHandlerInTable(int* data);
+
   // Determine the code for the frame.
   Code* unchecked_code() const override;
 
   // Accessors.
   Object* wasm_obj() const;
   uint32_t function_index() const;
   Script* script() const override;
 
   static WasmFrame* cast(StackFrame* frame) {
     DCHECK(frame->is_wasm());
@@ skipping 248 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_