[DevTools] Add unittest for upstream encoding library.

This brings in
third_party/inspector_protocol/encoding/encoding_test.cc
from the upstream project and makes it work for v8's
unittest suite.

encoding_test_helper.h is a V8 specific implementation,
which delegates to src/inspector/v8-string-conversions{.h,.cc},
for the utf8 / utf16 conversion routines.

I'm also fixing / updating roll.py, for future rolls.

Change-Id: I08e4784838ff81ef3ac328f783512b42c91b6bcd
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1597215Reviewed-by: Adam Klein <adamk@chromium.org>
Reviewed-by: Dmitry Gozman <dgozman@chromium.org>
Commit-Queue: Johannes Henkel <johannes@chromium.org>
Cr-Commit-Position: refs/heads/master@{#61393}

test/unittests/BUILD.gn

@@ -295,6 +295,7 @@ v8_source_set("unittests_sources") {
     "../..:v8_for_testing",
     "../..:v8_libbase",
     "../..:v8_libplatform",
+    "../../third_party/inspector_protocol:encoding_test",
     "//build/win:default_exe_manifest",
     "//testing/gmock",
     "//testing/gtest",

third_party/inspector_protocol/BUILD.gn

@@ -8,3 +8,27 @@ static_library("encoding") {
     "encoding/encoding.h",
   ]
 }
+
+# encoding_test is part of the unittests, defined in
+# test/unittests/BUILD.gn.
+
+import("../../gni/v8.gni")
+
+v8_source_set("encoding_test") {
+  sources = [
+    "encoding/encoding_test.cc",
+    "encoding/encoding_test_helper.h",
+  ]
+  configs = [
+    "../..:external_config",
+    "../..:internal_config_base",
+  ]
+  deps = [
+    ":encoding",
+    "../..:v8_libbase",
+    "../../src/inspector:inspector_string_conversions",
+    "//testing/gmock",
+    "//testing/gtest",
+  ]
+  testonly = true
+}

third_party/inspector_protocol/encoding/encoding.h

@@ -13,6 +13,7 @@
 #include <vector>
 
 namespace v8_inspector_protocol_encoding {
+
 // =============================================================================
 // span - sequence of bytes
 // =============================================================================

third_party/inspector_protocol/encoding/encoding_test_helper.h

+// Copyright 2019 The V8 Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// This file is V8 specific, to make encoding_test.cc work.
+// It is not rolled from the upstream project.
+
+#ifndef V8_INSPECTOR_PROTOCOL_ENCODING_ENCODING_TEST_HELPER_H_
+#define V8_INSPECTOR_PROTOCOL_ENCODING_ENCODING_TEST_HELPER_H_
+
+#include <string>
+#include <vector>
+
+#include "src/base/logging.h"
+#include "src/inspector/v8-string-conversions.h"
+#include "testing/gmock/include/gmock/gmock.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace v8_inspector_protocol_encoding {
+
+std::string UTF16ToUTF8(span<uint16_t> in) {
+  return v8_inspector::UTF16ToUTF8(in.data(), in.size());
+}
+
+std::vector<uint16_t> UTF8ToUTF16(span<uint8_t> in) {
+  std::basic_string<uint16_t> utf16 = v8_inspector::UTF8ToUTF16(
+      reinterpret_cast<const char*>(in.data()), in.size());
+  return std::vector<uint16_t>(utf16.begin(), utf16.end());
+}
+
+}  // namespace v8_inspector_protocol_encoding
+
+#endif  // V8_INSPECTOR_PROTOCOL_ENCODING_ENCODING_TEST_HELPER_H_

third_party/inspector_protocol/roll.py

@@ -18,6 +18,9 @@ FILES_TO_SYNC = [
     'code_generator.py',
     'concatenate_protocols.py',
     'convert_protocol_to_json.py',
+    'encoding/encoding.h',
+    'encoding/encoding.cc',
+    'encoding/encoding_test.cc',
     'inspector_protocol.gni',
     'inspector_protocol.gypi',
     'lib/*',