Avoid calling strlen() where possible in base/trace_config

base/trace_event/trace_event_etw_export_win.cc

 // Copyright 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_event_etw_export_win.h"
 
 #include <stddef.h>
 
 #include "base/command_line.h"
 #include "base/logging.h"
@@ skipping 330 matching lines @@
 void TraceEventETWExport::AddCompleteEndEvent(const char* name) {
   auto* instance = GetInstance();
   if (!instance || !instance->etw_export_enabled_ || !EventEnabledChromeEvent())
     return;
 
   EventWriteChromeEvent(name, "Complete End", "", "", "", "", "", "");
 }
 
 // static
 bool TraceEventETWExport::IsCategoryGroupEnabled(
-    const char* category_group_name) {
-  DCHECK(category_group_name);
+    StringPiece category_group_name) {
+  DCHECK(!category_group_name.empty());
   auto* instance = GetInstance();
   if (instance == nullptr)
     return false;
 
   if (!instance->IsETWExportEnabled())
     return false;
 
-  CStringTokenizer category_group_tokens(
-      category_group_name, category_group_name + strlen(category_group_name),
-      ",");
+  CStringTokenizer category_group_tokens(category_group_name.begin(),
+                                         category_group_name.end(), ",");
   while (category_group_tokens.GetNext()) {
-    std::string category_group_token = category_group_tokens.token();
-    if (instance->IsCategoryEnabled(category_group_token.c_str())) {
+    StringPiece category_group_token = category_group_tokens.token_piece();
+    if (instance->IsCategoryEnabled(category_group_token)) {
       return true;
     }
   }
   return false;
 }
 
 bool TraceEventETWExport::UpdateEnabledCategories() {
   if (etw_match_any_keyword_ == CHROME_Context.MatchAnyKeyword)
     return false;
 
@@ skipping 23 matching lines @@
   }
 
   DCHECK_EQ(kNumberOfCategories, categories_status_.size());
 
   // Update the categories in TraceLog.
   TraceLog::GetInstance()->UpdateETWCategoryGroupEnabledFlags();
 
   return true;
 }
 
-bool TraceEventETWExport::IsCategoryEnabled(const char* category_name) const {
+bool TraceEventETWExport::IsCategoryEnabled(StringPiece category_name) const {
   DCHECK_EQ(kNumberOfCategories, categories_status_.size());
   // Try to find the category and return its status if found
   auto it = categories_status_.find(category_name);
   if (it != categories_status_.end())
     return it->second;
 
   // Otherwise return the corresponding default status by first checking if the
   // category is disabled by default.
-  if (StringPiece(category_name).starts_with("disabled-by-default")) {
+  if (category_name.starts_with("disabled-by-default")) {
     DCHECK(categories_status_.find(kDisabledOtherEventsGroupName) !=
            categories_status_.end());
     return categories_status_.find(kDisabledOtherEventsGroupName)->second;
   } else {
     DCHECK(categories_status_.find(kOtherEventsGroupName) !=
            categories_status_.end());
     return categories_status_.find(kOtherEventsGroupName)->second;
   }
 }
 
 // static
 void TraceEventETWExport::UpdateETWKeyword() {
   if (!IsETWExportEnabled())
     return;
   auto* instance = GetInstance();
   DCHECK(instance);
   instance->UpdateEnabledCategories();
 }
 }  // namespace trace_event
 }  // namespace base