Change base class of V8SamplingProfiler to AsyncEnabledStateObserver.

content/renderer/devtools/v8_sampling_profiler.cc

Index: content/renderer/devtools/v8_sampling_profiler.cc
diff --git a/content/renderer/devtools/v8_sampling_profiler.cc b/content/renderer/devtools/v8_sampling_profiler.cc
index c27f29b6990317682b100d84ddfe5de6a22bd633..dd806a8ac90ada217dca07f6ff2f4a7507b6475f 100644
--- a/content/renderer/devtools/v8_sampling_profiler.cc
+++ b/content/renderer/devtools/v8_sampling_profiler.cc
@@ -580,18 +580,20 @@ void V8SamplingThread::Stop() {
 V8SamplingProfiler::V8SamplingProfiler(bool underTest)
     : sampling_thread_(nullptr),
       render_thread_sampler_(Sampler::CreateForCurrentThread()),
-      task_runner_(base::ThreadTaskRunnerHandle::Get()) {
+      task_runner_(base::ThreadTaskRunnerHandle::Get()),
+      weak_factory_(this) {
   DCHECK(underTest || RenderThreadImpl::current());
   // Force the "v8.cpu_profile*" categories to show up in the trace viewer.
   TraceLog::GetCategoryGroupEnabled(
       TRACE_DISABLED_BY_DEFAULT("v8.cpu_profile"));
   TraceLog::GetCategoryGroupEnabled(
       TRACE_DISABLED_BY_DEFAULT("v8.cpu_profile.hires"));
-  TraceLog::GetInstance()->AddEnabledStateObserver(this);
+  TraceLog::GetInstance()->AddAsyncEnabledStateObserver(
+      weak_factory_.GetWeakPtr());
 }
 
 V8SamplingProfiler::~V8SamplingProfiler() {
-  TraceLog::GetInstance()->RemoveEnabledStateObserver(this);
+  TraceLog::GetInstance()->RemoveAsyncEnabledStateObserver(this);
   DCHECK(!sampling_thread_.get());
 }