Only enable heap tracking under --enable-heap-profiling=task-profiler.

base/base_switches.cc

 // Copyright (c) 2012 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/base_switches.h"
 #include "build/build_config.h"
 
 namespace switches {
 
 // Disables the crash reporting.
 const char kDisableBreakpad[]               = "disable-breakpad";
 
 // Indicates that crash reporting should be enabled. On platforms where helper
 // processes cannot access to files needed to make this decision, this flag is
 // generated internally.
 const char kEnableCrashReporter[]           = "enable-crash-reporter";
 
 // Makes memory allocators keep track of their allocations and context, so a
 // detailed breakdown of memory usage can be presented in chrome://tracing when
 // the memory-infra category is enabled.
 const char kEnableHeapProfiling[]           = "enable-heap-profiling";
 
 // Report native (walk the stack) allocation traces. By default pseudo stacks
 // derived from trace events are reported.
 const char kEnableHeapProfilingModeNative[] = "native";
 
+// Report heap usage and churn in the task profiler (chrome://profiler).

[Primiano Tucci (use gerrit), 2017/02/15 14:18:03]

can you add: "Does not keep track of individual allocations unlike the default
and native mode. Keeps only track of summarized churn stats in the task profiler
(chrome://profiler)"

[Sigurður Ásgeirsson, 2017/02/15 15:35:45]

Done.

+const char kEnableHeapProfilingTaskProfiler[] = "task-profiler";
+
 // Generates full memory crash dump.
 const char kFullMemoryCrashReport[]         = "full-memory-crash-report";
 
 // Force low-end device mode when set.
 const char kEnableLowEndDeviceMode[]        = "enable-low-end-device-mode";
 
 // Force disabling of low-end device mode when set.
 const char kDisableLowEndDeviceMode[]       = "disable-low-end-device-mode";
 
 // This option can be used to force field trials when testing changes locally.
@@ skipping 68 matching lines @@
 #endif
 
 #if defined(OS_POSIX)
 // Used for turning on Breakpad crash reporting in a debug environment where
 // crash reporting is typically compiled but disabled.
 const char kEnableCrashReporterForTesting[] =
     "enable-crash-reporter-for-testing";
 #endif
 
 }  // namespace switches