[tracing] Add test for memory-infra startup tracing

base/trace_event/memory_dump_manager.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/memory_dump_manager.h"
 
 #include <algorithm>
 
 #include "base/atomic_sequence_num.h"
 #include "base/command_line.h"
@@ skipping 38 matching lines @@
 
 void RequestPeriodicGlobalDump() {
   MemoryDumpArgs::LevelOfDetail dump_level_of_detail;
   if (g_heavy_dumps_rate == 0) {
     dump_level_of_detail = MemoryDumpArgs::LevelOfDetail::LOW;
   } else {
     dump_level_of_detail = g_periodic_dumps_count == 0
                                ? MemoryDumpArgs::LevelOfDetail::HIGH
                                : MemoryDumpArgs::LevelOfDetail::LOW;
 
-    if (++g_periodic_dumps_count == g_heavy_dumps_rate - 1)
+    if (++g_periodic_dumps_count == g_heavy_dumps_rate)
       g_periodic_dumps_count = 0;
   }
 
   MemoryDumpArgs dump_args = {dump_level_of_detail};
   MemoryDumpManager::GetInstance()->RequestGlobalDump(
       MemoryDumpType::PERIODIC_INTERVAL, dump_args);
 }
 
 }  // namespace
 
@@ skipping 32 matching lines @@
   if (instance)
     instance->skip_core_dumpers_auto_registration_for_testing_ = true;
   g_instance_for_testing = instance;
 }
 
 MemoryDumpManager::MemoryDumpManager()
     : delegate_(nullptr),
       is_coordinator_(false),
       memory_tracing_enabled_(0),
       tracing_process_id_(kInvalidTracingProcessId),
-      skip_core_dumpers_auto_registration_for_testing_(false),
-      disable_periodic_dumps_for_testing_(false) {
+      skip_core_dumpers_auto_registration_for_testing_(false) {
   g_next_guid.GetNext();  // Make sure that first guid is not zero.
 }
 
 MemoryDumpManager::~MemoryDumpManager() {
   TraceLog::GetInstance()->RemoveEnabledStateObserver(this);
 }
 
 void MemoryDumpManager::Initialize(MemoryDumpManagerDelegate* delegate,
                                    bool is_coordinator) {
   {
@@ skipping 295 matching lines @@
   for (auto it = dump_providers_.begin(); it != dump_providers_.end(); ++it) {
     it->disabled = false;
     it->consecutive_failures = 0;
   }
 
   subtle::NoBarrier_Store(&memory_tracing_enabled_, 1);
 
   // TODO(primiano): This is a temporary hack to disable periodic memory dumps
   // when running memory benchmarks until telemetry uses TraceConfig to
   // enable/disable periodic dumps. See crbug.com/529184 .
-  // The same mechanism should be used to disable periodic dumps in tests.
   if (!is_coordinator_ ||
       CommandLine::ForCurrentProcess()->HasSwitch(
-          "enable-memory-benchmarking") ||
-      disable_periodic_dumps_for_testing_) {
+          "enable-memory-benchmarking")) {
     return;
   }
 
   // Enable periodic dumps. At the moment the periodic support is limited to at
   // most one low-detail periodic dump and at most one high-detail periodic
   // dump. If both are specified the high-detail period must be an integer
   // multiple of the low-level one.
   g_periodic_dumps_count = 0;
   const TraceConfig trace_config =
       TraceLog::GetInstance()->GetCurrentTraceConfig();
@@ skipping 60 matching lines @@
       next_dump_provider(next_dump_provider),
       callback(callback),
       task_runner(MessageLoop::current()->task_runner()) {
 }
 
 MemoryDumpManager::ProcessMemoryDumpAsyncState::~ProcessMemoryDumpAsyncState() {
 }
 
 }  // namespace trace_event
 }  // namespace base