WebAssembly: add stack trace test

The test currently only shows the JavaScript stack frames, I'll then add
support for interleaved WebAssembly stack frames and update the test.

R=titzer@chromium.org

Review URL: https://codereview.chromium.org/1661383002

Cr-Commit-Position: refs/heads/master@{#33742}

test/mjsunit/wasm/stack.js

+// 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.
+
+// Flags: --expose-wasm
+
+load("test/mjsunit/wasm/wasm-constants.js");
+
+function testStack(func, check) {
+  var kBodySize = 2;
+  var kNameFunOffset = 22 + kBodySize + 1;
+  var kNameMainOffset = kNameFunOffset + 4;
+
+  var ffi = new Object();
+  ffi.fun = func;
+
+  var data = bytes(
+      // signatures
+      kDeclSignatures, 1,  //  --
+      0, kAstStmt,         // () -> void
+      // -- foreign function
+      kDeclFunctions, 2,                        //  --
+      kDeclFunctionName | kDeclFunctionImport,  // --
+      0, 0,                                     //  --
+      kNameFunOffset, 0, 0, 0,                  // name offset
+      // -- main function
+      kDeclFunctionName | kDeclFunctionExport,  // --
+      0, 0,                                     //  --
+      kNameMainOffset, 0, 0, 0,                 // name offset
+      kBodySize, 0,
+      // main body
+      kExprCallFunction, 0,  // --
+      // names
+      kDeclEnd,              //  --
+      'f', 'u', 'n', 0,      //  --
+      'm', 'a', 'i', 'n', 0  //  --
+      );
+
+  var module = _WASMEXP_.instantiateModule(data, ffi);
+
+  assertEquals("function", typeof module.main);
+
+  module.main();
+  check();
+}
+
+// The stack trace contains file path, only keep "stack.js".
+function stripPath(s) {
+  return s.replace(/[^ (]*stack\.js/g, "stack.js");
+}
+
+var stack;
+function STACK() {
+  var e = new Error();
+  stack = e.stack;
+}
+
+function check_STACK() {
+  assertEquals(expected, stripPath(stack));
+}
+
+var expected = "Error\n" +
+    // The line numbers below will change as this test gains / loses lines..
+    "    at STACK (stack.js:54:11)\n" +  // --
+    "    at testStack (stack.js:43:10)\n" +
+    // TODO(jfb) Add WebAssembly stack here.
+    "    at stack.js:69:1";
+
+testStack(STACK, check_STACK);