[DevTools] Migrate v8_inspector/public from String16 to String{View,Buffer}.

third_party/WebKit/Source/platform/v8_inspector/public/String.h

+// 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 String_h
+#define String_h
+
+#include "platform/PlatformExport.h"
+
+#include <cctype>
+#include <memory>
+#include <stdint.h>
+
+namespace v8_inspector {
+
+class PLATFORM_EXPORT StringView {
+public:
+    StringView() : m_is8Bit(true), m_length(0) { m_characters8 = nullptr; }
+    StringView(const uint8_t* characters, unsigned length) : m_is8Bit(true), m_length(length) { m_characters8 = characters; }

[esprehn, 2016/08/23 17:35:39]

you can just initialize an unnamed union member directly, 

m_characters8(characters)

[dgozman, 2016/08/24 00:45:01]

Done.

+    StringView(const uint16_t* characters, unsigned length) : m_is8Bit(false), m_length(length) { m_characters16 = characters; }

[esprehn, 2016/08/23 17:35:39]

ditto

+
+    bool is8Bit() const { return m_is8Bit; }
+    unsigned length() const { return m_length; }
+    const uint8_t* characters8() const { return m_characters8; }

[esprehn, 2016/08/23 17:35:39]

DCHECK(m_is8Bit)

[dgozman, 2016/08/24 00:45:01]

Unfortunately, I cannot do that right now, since it requires wtf/Assertions.h
include in this public header which is unacceptable. I think we can do it after
moving to v8 though.

+    const uint16_t* characters16() const { return m_characters16; }

[esprehn, 2016/08/23 17:35:39]

DCHECK(!m_is8Bit)

+
+private:
+    bool m_is8Bit;
+    unsigned m_length;
+    union {
+        const uint8_t* m_characters8;
+        const uint16_t* m_characters16;
+    };
+};
+
+class PLATFORM_EXPORT StringBuffer {

[esprehn, 2016/08/23 17:35:39]

can we put these in separate headers? StringView.h and StringBuffer.h ?

[dgozman, 2016/08/24 00:45:01]

Sure.

+public:
+    virtual ~StringBuffer() { }
+    virtual const StringView& string() = 0;
+    // This method copies contents.
+    static std::unique_ptr<StringBuffer> create(const StringView&);
+};
+
+} // namespace v8_inspector
+
+#endif // String_h