[wasm] Add inspector test for stepping

src/wasm/wasm-interpreter.cc

 // Copyright 2016 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/wasm/wasm-interpreter.h"
 
 #include "src/utils.h"
 #include "src/wasm/decoder.h"
 #include "src/wasm/function-body-decoder.h"
 #include "src/wasm/wasm-external-refs.h"
@@ skipping 1185 matching lines @@
       const char* skip = "        ";
       int len = 1;
       byte opcode = code->start[pc];
       byte orig = opcode;
       if (V8_UNLIKELY(opcode == kInternalBreakpoint)) {
         orig = code->orig_start[pc];
         if (SkipBreakpoint(code, pc)) {
           // skip breakpoint by switching on original code.
           skip = "[skip]  ";
         } else {
-          state_ = WasmInterpreter::PAUSED;
           TRACE("@%-3zu: [break] %-24s:", pc,
                 WasmOpcodes::OpcodeName(static_cast<WasmOpcode>(orig)));
           TraceValueStack();
           TRACE("\n");
-          break_pc_ = pc;
-          return CommitPc(pc);
+          break;
         }
       }
 
       USE(skip);
       TRACE("@%-3zu: %s%-24s:", pc, skip,
             WasmOpcodes::OpcodeName(static_cast<WasmOpcode>(orig)));
       TraceValueStack();
       TRACE("\n");
 
       switch (orig) {
@@ skipping 408 matching lines @@
 #undef EXECUTE_OTHER_UNOP_NAN
 
         default:
           V8_Fatal(__FILE__, __LINE__, "Unknown or unimplemented opcode #%d:%s",
                    code->start[pc], OpcodeName(code->start[pc]));
           UNREACHABLE();
       }
 
       pc += len;
     }
+    // Set break_pc_, even though we might have stopped because max was reached.
+    // We don't want to stop after executing zero instructions next time.
+    break_pc_ = pc;
     state_ = WasmInterpreter::PAUSED;
     CommitPc(pc);
   }
 
   WasmVal Pop() {
     DCHECK_GT(stack_.size(), 0);
     DCHECK_GT(frames_.size(), 0);
     DCHECK_GT(stack_.size(), frames_.back().llimit());  // can't pop into locals
     WasmVal val = stack_.back();
     stack_.pop_back();
@@ skipping 270 matching lines @@
   return none;
 }
 
 void InterpretedFrame::SetLocalVal(int index, WasmVal val) { UNIMPLEMENTED(); }
 
 void InterpretedFrame::SetExprVal(int pc, WasmVal val) { UNIMPLEMENTED(); }
 
 }  // namespace wasm
 }  // namespace internal
 }  // namespace v8