Revert of DevTools: use explicit IPC messages for enabling/disabling tracing instead of intercepting protocol…

content/browser/devtools/devtools_tracing_handler.cc

Index: content/browser/devtools/devtools_tracing_handler.cc
diff --git a/content/browser/devtools/devtools_tracing_handler.cc b/content/browser/devtools/devtools_tracing_handler.cc
index 238cf24d5f8d2f8b8f4bc31a90126e0254cb4e60..de81bf3cb6ad3b3f556c7cb779e8cb464007d2d4 100644
--- a/content/browser/devtools/devtools_tracing_handler.cc
+++ b/content/browser/devtools/devtools_tracing_handler.cc
@@ -64,6 +64,12 @@
                                     base::Unretained(this)));
   RegisterCommandHandler(devtools::Tracing::getCategories::kName,
                          base::Bind(&DevToolsTracingHandler::OnGetCategories,
+                                    base::Unretained(this)));
+  RegisterNotificationHandler(devtools::Tracing::started::kName,
+                         base::Bind(&DevToolsTracingHandler::OnTracingStarted,
+                                    base::Unretained(this)));
+  RegisterNotificationHandler(devtools::Tracing::stopped::kName,
+                         base::Bind(&DevToolsTracingHandler::OnTracingStopped,
                                     base::Unretained(this)));
 }
 
@@ -148,11 +154,6 @@
 scoped_refptr<DevToolsProtocol::Response>
 DevToolsTracingHandler::OnStart(
     scoped_refptr<DevToolsProtocol::Command> command) {
-  // If inspected target is a render process Tracing.start will be handled by
-  // tracing agent in the renderer.
-  if (target_ == Renderer)
-    return NULL;
-
   is_recording_ = true;
 
   std::string categories;
@@ -173,6 +174,16 @@
   }
 
   SetupTimer(usage_reporting_interval);
+
+  // If inspected target is a render process Tracing.start will be handled by
+  // tracing agent in the renderer.
+  if (target_ == Renderer) {
+    TracingController::GetInstance()->EnableRecording(
+        base::debug::CategoryFilter(categories),
+        options,
+        TracingController::EnableRecordingDoneCallback());
+    return NULL;
+  }
 
   TracingController::GetInstance()->EnableRecording(
       base::debug::CategoryFilter(categories),
@@ -217,10 +228,6 @@
 scoped_refptr<DevToolsProtocol::Response>
 DevToolsTracingHandler::OnEnd(
     scoped_refptr<DevToolsProtocol::Command> command) {
-  // If inspected target is a render process Tracing.end will be handled by
-  // tracing agent in the renderer.
-  if (target_ == Renderer)
-    return NULL;
   DisableRecording(
       base::Bind(&DevToolsTracingHandler::BeginReadingRecordingResult,
                  weak_factory_.GetWeakPtr()));
@@ -265,7 +272,8 @@
   SendAsyncResponse(command->SuccessResponse(response));
 }
 
-void DevToolsTracingHandler::EnableTracing(const std::string& category_filter) {
+void DevToolsTracingHandler::OnTracingStarted(
+    scoped_refptr<DevToolsProtocol::Notification> notification) {
   if (is_recording_)
     return;
   is_recording_ = true;
@@ -273,13 +281,13 @@
   SetupTimer(kDefaultReportingInterval);
 
   TracingController::GetInstance()->EnableRecording(
-      base::debug::CategoryFilter(category_filter),
+      base::debug::CategoryFilter(kDefaultCategories),
       base::debug::TraceOptions(),
       TracingController::EnableRecordingDoneCallback());
-  SendNotification(devtools::Tracing::started::kName, NULL);
-}
-
-void DevToolsTracingHandler::DisableTracing() {
+}
+
+void DevToolsTracingHandler::OnTracingStopped(
+    scoped_refptr<DevToolsProtocol::Notification> notification) {
   if (!is_recording_)
     return;
   is_recording_ = false;