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

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

Index: third_party/WebKit/Source/platform/v8_inspector/V8StringUtil.cpp
diff --git a/third_party/WebKit/Source/platform/v8_inspector/V8StringUtil.cpp b/third_party/WebKit/Source/platform/v8_inspector/V8StringUtil.cpp
index 69c92e4b799e29e64fe22da259c49667134cbc15..f17d971fe335e8d38457892197b654e85bdc116b 100644
--- a/third_party/WebKit/Source/platform/v8_inspector/V8StringUtil.cpp
+++ b/third_party/WebKit/Source/platform/v8_inspector/V8StringUtil.cpp
@@ -136,12 +136,20 @@ PassOwnPtr<V8Regex> createSearchRegex(V8DebuggerImpl* debugger, const String& qu
 
 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)