Add ui devtools server

ui/devtools/StringUtil.h

Index: ui/devtools/StringUtil.h
diff --git a/ui/devtools/StringUtil.h b/ui/devtools/StringUtil.h
new file mode 100644
index 0000000000000000000000000000000000000000..8c61ffad506c7d988f850773e1bd6f13ee494467
--- /dev/null
+++ b/ui/devtools/StringUtil.h
@@ -0,0 +1,58 @@
+// Copyright 2016 The Chromium 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 WS_STRINGUTIL_H_
+#define WS_STRINGUTIL_H_
+
+#include <memory>
+
+#include "base/json/json_reader.h"
+#include "base/strings/string_number_conversions.h"
+
+namespace ui {
+namespace devtools {
+
+using String = std::string;
+
+namespace protocol {
+
+class Value;
+
+std::unique_ptr<Value> parseJSON(const String& string);
+
+class CustomStringBuilder {
+  String s_;
+
+ public:
+  CustomStringBuilder() : s_("") {}
+  CustomStringBuilder(String& s) : s_(s) {}
+  void reserveCapacity(std::size_t size) { s_.reserve(size); }
+  void append(const String& s) { s_ += s; }
+  void append(char c) { s_ += c; }
+  void append(const char*, unsigned int length) { return; }
+  String toString() { return s_; }
+};
+
+using StringBuilder = CustomStringBuilder;
+
+class StringUtil {
+ public:
+  static String substring(const String& s, unsigned pos, unsigned len) {
+    return s.substr(pos, len);
+  }
+  static String fromInteger(int number) { return base::IntToString(number); }
+  static String fromDouble(double number) {
+    return base::DoubleToString(number);
+  }
+  static void builderReserve(StringBuilder& builder, unsigned capacity) {
+    builder.reserveCapacity(capacity);
+  }
+  static const size_t kNotFound = -1;
+};
+
+}  // namespace protocol
+}  // namespace devtools
+}  // namespace ui
+
+#endif  // WS_STRINGUTIL_H_