tracing: split trace event filter classes out of TraceLog

base/trace_event/trace_config.cc

 // Copyright (c) 2015 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 "base/trace_event/trace_config.h"
 
 #include <stddef.h>
 
 #include <utility>
 
@@ skipping 151 matching lines @@
 void TraceConfig::EventFilterConfig::AddExcludedCategory(
     const std::string& category) {
   excluded_categories_.push_back(category);
 }
 
 void TraceConfig::EventFilterConfig::SetArgs(
     std::unique_ptr<base::DictionaryValue> args) {
   args_ = std::move(args);
 }
 
+bool TraceConfig::EventFilterConfig::GetArgAsSet(
+    const char* key,
+    std::unordered_set<std::string>* out_set) const {
+  const ListValue* list = nullptr;
+  if (!args_->GetList(key, &list))
+    return false;
+  for (size_t i = 0; i < list->GetSize(); ++i) {
+    std::string value;
+    if (list->GetString(i, &value))
+      out_set->insert(value);
+  }
+  return true;
+}
+
 bool TraceConfig::EventFilterConfig::IsCategoryGroupEnabled(
     const char* category_group_name) const {
   CStringTokenizer category_group_tokens(
       category_group_name, category_group_name + strlen(category_group_name),
       ",");
   while (category_group_tokens.GetNext()) {
     std::string category_group_token = category_group_tokens.token();
 
     for (const auto& excluded_category : excluded_categories_) {
       if (base::MatchPattern(category_group_token, excluded_category)) {
@@ skipping 667 matching lines @@
     StringPiece str) {
   return str.empty() || str.front() == ' ' || str.back() == ' ';
 }
 
 bool TraceConfig::HasIncludedPatterns() const {
   return !included_categories_.empty();
 }
 
 }  // namespace trace_event
 }  // namespace base