AddClockSyncMetadataEvent on Android

This was accidentally deleted in crrev.com/c/575716.

Bug: 797809
Change-Id: I360915247c8fc093beed2426b760ec680cd50ccb
Reviewed-on: https://chromium-review.googlesource.com/949977Reviewed-by: John Abd-El-Malek <jam@chromium.org>
Reviewed-by: oysteine <oysteine@chromium.org>
Reviewed-by: Charlie Andrews <charliea@chromium.org>
Commit-Queue: Ehsan Chiniforooshan <chiniforooshan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#544352}

content/browser/tracing/tracing_controller_impl.cc

@@ -146,8 +146,8 @@ void TracingControllerImpl::AddAgents() {
   agents_.push_back(std::make_unique<EtwTracingAgent>(connector));
 #endif
 
-  auto chrome_agent =
-      std::make_unique<tracing::ChromeTraceEventAgent>(connector);
+  auto chrome_agent = std::make_unique<tracing::ChromeTraceEventAgent>(
+      connector, true /* request_clock_sync_marker_on_android */);
   // For adding general CPU, network, OS, and other system information to the
   // metadata.
   chrome_agent->AddMetadataGeneratorFunction(base::BindRepeating(

content/child/child_thread_impl.cc

@@ -603,8 +603,8 @@ void ChildThreadImpl::InitTracing() {
   channel_->AddFilter(new tracing::ChildTraceMessageFilter(
       ChildProcess::current()->io_task_runner()));
 
-  chrome_trace_event_agent_ =
-      std::make_unique<tracing::ChromeTraceEventAgent>(GetConnector());
+  chrome_trace_event_agent_ = std::make_unique<tracing::ChromeTraceEventAgent>(
+      GetConnector(), false /* request_clock_sync_marker_on_android */);
 }
 
 ChildThreadImpl::~ChildThreadImpl() {

services/tracing/public/cpp/chrome_trace_event_agent.cc

@@ -16,6 +16,7 @@
 #include "base/time/time.h"
 #include "base/trace_event/trace_log.h"
 #include "base/values.h"
+#include "build/build_config.h"
 #include "services/service_manager/public/cpp/connector.h"
 #include "services/tracing/public/mojom/constants.mojom.h"
 
@@ -35,11 +36,16 @@ ChromeTraceEventAgent* ChromeTraceEventAgent::GetInstance() {
 }
 
 ChromeTraceEventAgent::ChromeTraceEventAgent(
-    service_manager::Connector* connector)
+    service_manager::Connector* connector,
+    bool request_clock_sync_marker_on_android)
     : BaseAgent(connector,
                 kChromeTraceEventLabel,
                 mojom::TraceDataType::ARRAY,
-                false /* supports_explicit_clock_sync */),
+#if defined(OS_ANDROID)
+                request_clock_sync_marker_on_android),
+#else
+                false),
+#endif
       enabled_tracing_modes_(0) {
   DCHECK_CALLED_ON_VALID_THREAD(thread_checker_);
   DCHECK(!g_chrome_trace_event_agent);
@@ -93,6 +99,17 @@ void ChromeTraceEventAgent::StopAndFlush(mojom::RecorderPtr recorder) {
       &ChromeTraceEventAgent::OnTraceLogFlush, base::Unretained(this)));
 }
 
+void ChromeTraceEventAgent::RequestClockSyncMarker(
+    const std::string& sync_id,
+    const Agent::RequestClockSyncMarkerCallback& callback) {
+#if defined(OS_ANDROID)
+  base::trace_event::TraceLog::GetInstance()->AddClockSyncMetadataEvent();
+  callback.Run(base::TimeTicks(), base::TimeTicks());
+#else
+  NOTREACHED();
+#endif
+}
+
 void ChromeTraceEventAgent::RequestBufferStatus(
     const RequestBufferStatusCallback& callback) {
   base::trace_event::TraceLogStatus status =

services/tracing/public/cpp/chrome_trace_event_agent.h

@@ -34,7 +34,8 @@ class COMPONENT_EXPORT(TRACING_CPP) ChromeTraceEventAgent : public BaseAgent {
 
   static ChromeTraceEventAgent* GetInstance();
 
-  explicit ChromeTraceEventAgent(service_manager::Connector* connector);
+  explicit ChromeTraceEventAgent(service_manager::Connector* connector,
+                                 bool request_clock_sync_marker_on_android);
 
   void AddMetadataGeneratorFunction(MetadataGeneratorFunction generator);
 
@@ -49,6 +50,9 @@ class COMPONENT_EXPORT(TRACING_CPP) ChromeTraceEventAgent : public BaseAgent {
                     base::TimeTicks coordinator_time,
                     const StartTracingCallback& callback) override;
   void StopAndFlush(mojom::RecorderPtr recorder) override;
+  void RequestClockSyncMarker(
+      const std::string& sync_id,
+      const Agent::RequestClockSyncMarkerCallback& callback) override;
   void RequestBufferStatus(
       const RequestBufferStatusCallback& callback) override;
   void GetCategories(const GetCategoriesCallback& callback) override;

services/tracing/public/cpp/chrome_trace_event_agent_unittest.cc

@@ -83,7 +83,7 @@ class ChromeTraceEventAgentTest : public testing::Test {
  public:
   void SetUp() override {
     message_loop_.reset(new base::MessageLoop());
-    agent_.reset(new ChromeTraceEventAgent(nullptr));
+    agent_.reset(new ChromeTraceEventAgent(nullptr, false));
   }
 
   void TearDown() override {