DevTools: [regression] do not go back and forth via utf8 in the debugger/runtime agents.

third_party/WebKit/Source/platform/v8_inspector/V8StringUtil.cpp

 // 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.
 
 #include "platform/v8_inspector/V8StringUtil.h"
 
 #include "platform/v8_inspector/V8DebuggerImpl.h"
 #include "platform/v8_inspector/V8Regex.h"
 #include "platform/v8_inspector/public/V8ContentSearchUtil.h"
 #include "wtf/text/StringBuilder.h"
@@ skipping 135 matching lines @@
 PassOwnPtr<V8Regex> createSearchRegex(V8DebuggerImpl* debugger, const String& query, bool caseSensitive, bool isRegex)
 {
     String regexSource = isRegex ? query : createSearchRegexSource(query);
     return adoptPtr(new V8Regex(debugger, regexSource, caseSensitive ? TextCaseSensitive : TextCaseInsensitive));
 }
 
 } // namespace
 
 v8::Local<v8::String> toV8String(v8::Isolate* isolate, const String& string)
 {
-    return v8::String::NewFromUtf8(isolate, string.utf8().data(), v8::NewStringType::kNormal).ToLocalChecked();
+    if (string.isNull())
+        return v8::String::Empty(isolate);
+    if (string.is8Bit())
+        return v8::String::NewFromOneByte(isolate, string.characters8(), v8::NewStringType::kNormal, string.length()).ToLocalChecked();
+    return v8::String::NewFromTwoByte(isolate, reinterpret_cast<const uint16_t*>(string.characters16()), v8::NewStringType::kNormal, string.length()).ToLocalChecked();
 }
 
 v8::Local<v8::String> toV8StringInternalized(v8::Isolate* isolate, const String& string)
 {
-    return v8::String::NewFromUtf8(isolate, string.utf8().data(), v8::NewStringType::kInternalized).ToLocalChecked();
+    if (string.isNull())
+        return v8::String::Empty(isolate);
+    if (string.is8Bit())
+        return v8::String::NewFromOneByte(isolate, string.characters8(), v8::NewStringType::kInternalized, string.length()).ToLocalChecked();
+    return v8::String::NewFromTwoByte(isolate, reinterpret_cast<const uint16_t*>(string.characters16()), v8::NewStringType::kInternalized, string.length()).ToLocalChecked();
 }
 
 String toWTFString(v8::Local<v8::String> value)
 {
     if (value.IsEmpty() || value->IsNull() || value->IsUndefined())
         return String();
     UChar* buffer;
     String result = String::createUninitialized(value->Length(), buffer);
     value->Write(reinterpret_cast<uint16_t*>(buffer), 0, value->Length());
     return result;
@@ skipping 26 matching lines @@
 
     for (const auto& match : matches)
         result->addItem(buildObjectForSearchMatch(match.first, match.second));
 
     return result.release();
 }
 
 } // namespace V8ContentSearchUtil
 
 } // namespace blink