src: rename confusingly named local variable

Rename `val_` to `string`.  The underscore suffix is normally reserved
for data members, not locals, and it's not a great name in the first
place.

PR-URL: #1042
Reviewed-By: Trevor Norris <trev.norris@gmail.com>

src/util.cc

@@ -8,20 +8,20 @@ Utf8Value::Utf8Value(v8::Isolate* isolate, v8::Handle<v8::Value> value)
   if (value.IsEmpty())
     return;
 
-  v8::Local<v8::String> val_ = value->ToString(isolate);
-  if (val_.IsEmpty())
+  v8::Local<v8::String> string = value->ToString(isolate);
+  if (string.IsEmpty())
     return;
 
   // Allocate enough space to include the null terminator
-  size_t len = StringBytes::StorageSize(val_, UTF8) + 1;
+  size_t len = StringBytes::StorageSize(string, UTF8) + 1;
   if (len > sizeof(str_st_)) {
     str_ = static_cast<char*>(malloc(len));
     CHECK_NE(str_, nullptr);
   }
 
   const int flags =
       v8::String::NO_NULL_TERMINATION | v8::String::REPLACE_INVALID_UTF8;
-  length_ = val_->WriteUtf8(str_, len, 0, flags);
+  length_ = string->WriteUtf8(str_, len, 0, flags);
   str_[length_] = '\0';
 }