DevTools: always use 16bit strings for inspector protocol.

third_party/WebKit/Source/platform/v8_inspector/V8DebuggerImpl.cpp

Index: third_party/WebKit/Source/platform/v8_inspector/V8DebuggerImpl.cpp
diff --git a/third_party/WebKit/Source/platform/v8_inspector/V8DebuggerImpl.cpp b/third_party/WebKit/Source/platform/v8_inspector/V8DebuggerImpl.cpp
index c5601c94bc914f099d7fd1d8f318afc5880c9f50..ee2834183de505ebe48585d419032fa95c2a6d7e 100644
--- a/third_party/WebKit/Source/platform/v8_inspector/V8DebuggerImpl.cpp
+++ b/third_party/WebKit/Source/platform/v8_inspector/V8DebuggerImpl.cpp
@@ -144,7 +144,7 @@ static int getGroupId(v8::Local<v8::Context> context)
     size_t commaPos = dataString.find(",");
     if (commaPos == kNotFound)
         return 0;
-    return dataString.left(commaPos).toInt();
+    return dataString.substring(0, commaPos).toInt();
 }
 
 void V8DebuggerImpl::addAgent(int contextGroupId, V8DebuggerAgentImpl* agent)