Reapply "Remove TraceController"

This reverts https://codereview.chromium.org/101543004/ which was created when
suspected the reason of failure of telemetry tests, but turned out not the real
reason. Reapply.

Reapply the following change:

> Revert "Revert 237280 "Remove TraceController""
>
> This reverts commit 6aa58b8599840160df945afa89e7482d14d1c4d4.
>
> Fixed double-close issue when ending recording.
>
> > Revert 237280 "Remove TraceController"
> >
> > Seems to have broken trace-based telemetry benchmarks on android.
> >
> > BUG=323749
> >
> > > Remove TraceController
> > >
> > > TraceController is obsoleted by TracingController.
> > > Changed all remaining clients to use TracingController.
> > >
> > > BUG=none
> > >
> > > Review URL: https://codereview.chromium.org/67683003
> >
> > TBR=wangxianzhu@chromium.org
> >
> > Review URL: https://codereview.chromium.org/89753004
> >
> > git-svn-id: svn://svn.chromium.org/chrome/trunk/src@237452 0039d316-1c4b-4281-b951-d872f2087c98
>
> TBR=wangxianzhu@chromium.org
>
> Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=238234

TBR=

Review URL: https://codereview.chromium.org/102003003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@238442 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 50 insertions, 30 deletions

diff --git a/chrome/test/base/tracing.cc b/chrome/test/base/tracing.cc
index 7060b9b..5aa07e7 100644
--- a/chrome/test/base/tracing.cc
+++ b/chrome/test/base/tracing.cc
@@ -4,19 +4,21 @@
 
 #include "chrome/test/base/tracing.h"
 
-#include "base/debug/trace_event.h"
+#include "base/file_util.h"
+#include "base/files/file_path.h"
 #include "base/memory/singleton.h"
 #include "base/message_loop/message_loop.h"
+#include "base/strings/string_util.h"
+#include "base/timer/timer.h"
 #include "content/public/browser/browser_thread.h"
-#include "content/public/browser/trace_controller.h"
-#include "content/public/browser/trace_subscriber.h"
+#include "content/public/browser/tracing_controller.h"
 #include "content/public/test/test_utils.h"
 
 namespace {
 
 using content::BrowserThread;
 
-class InProcessTraceController : public content::TraceSubscriber {
+class InProcessTraceController {
  public:
   static InProcessTraceController* GetInstance() {
     return Singleton<InProcessTraceController>::get();
@@ -29,8 +31,10 @@ class InProcessTraceController : public content::TraceSubscriber {
 
   bool BeginTracing(const std::string& category_patterns) {
     DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
-    return content::TraceController::GetInstance()->BeginTracing(
-        this, category_patterns, base::debug::TraceLog::RECORD_UNTIL_FULL);
+    return content::TracingController::GetInstance()->EnableRecording(
+        category_patterns, content::TracingController::DEFAULT_OPTIONS,
+        content::TracingController::EnableRecordingDoneCallback());
+    return true;
   }
 
   bool BeginTracingWithWatch(const std::string& category_patterns,
@@ -40,9 +44,11 @@ class InProcessTraceController : public content::TraceSubscriber {
     DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
     DCHECK(num_occurrences > 0);
     watch_notification_count_ = num_occurrences;
-    return BeginTracing(category_patterns) &&
-           content::TraceController::GetInstance()->SetWatchEvent(
-               this, category_name, event_name);
+    return content::TracingController::GetInstance()->SetWatchEvent(
+        category_name, event_name,
+        base::Bind(&InProcessTraceController::OnWatchEventMatched,
+                   base::Unretained(this))) &&
+        BeginTracing(category_patterns);
   }
 
   bool WaitForWatchEvent(base::TimeDelta timeout) {
@@ -67,20 +73,16 @@ class InProcessTraceController : public content::TraceSubscriber {
     DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
     using namespace base::debug;
 
-    TraceResultBuffer::SimpleOutput output;
-    trace_buffer_.SetOutputCallback(output.GetCallback());
-
-    trace_buffer_.Start();
-    if (!content::TraceController::GetInstance()->EndTracingAsync(this))
+    if (!content::TracingController::GetInstance()->DisableRecording(
+        base::FilePath(),
+        base::Bind(&InProcessTraceController::OnTraceDataCollected,
+                   base::Unretained(this),
+                   base::Unretained(json_trace_output))))
       return false;
+
     // Wait for OnEndTracingComplete() to quit the message loop.
-    // OnTraceDataCollected may be called multiple times while blocking here.
     message_loop_runner_ = new content::MessageLoopRunner;
     message_loop_runner_->Run();
-    trace_buffer_.Finish();
-    trace_buffer_.SetOutputCallback(TraceResultBuffer::OutputCallback());
-
-    *json_trace_output = output.json_output;
 
     // Watch notifications can occur during this method's message loop run, but
     // not after, so clear them here.
@@ -91,19 +93,40 @@ class InProcessTraceController : public content::TraceSubscriber {
  private:
   friend struct DefaultSingletonTraits<InProcessTraceController>;
 
-  // TraceSubscriber implementation
-  virtual void OnEndTracingComplete() OVERRIDE {
+  void OnEndTracingComplete() {
     message_loop_runner_->Quit();
   }
 
-  // TraceSubscriber implementation
-  virtual void OnTraceDataCollected(
-      const scoped_refptr<base::RefCountedString>& trace_fragment) OVERRIDE {
-    trace_buffer_.AddFragment(trace_fragment->data());
+  void OnTraceDataCollected(std::string* json_trace_output,
+                            const base::FilePath& path) {
+    BrowserThread::PostTask(BrowserThread::FILE, FROM_HERE,
+        base::Bind(&InProcessTraceController::ReadTraceData,
+                   base::Unretained(this),
+                   base::Unretained(json_trace_output),
+                   path));
   }
 
-  // TraceSubscriber implementation
-  virtual void OnEventWatchNotification() OVERRIDE {
+  void ReadTraceData(std::string* json_trace_output,
+                     const base::FilePath& path) {
+    json_trace_output->clear();
+    bool ok = base::ReadFileToString(path, json_trace_output);
+    DCHECK(ok);
+    base::DeleteFile(path, false);
+
+    // The callers expect an array of trace events.
+    const char* preamble = "{\"traceEvents\": ";
+    const char* trailout = "}";
+    DCHECK(StartsWithASCII(*json_trace_output, preamble, true));
+    DCHECK(EndsWith(*json_trace_output, trailout, true));
+    json_trace_output->erase(0, strlen(preamble));
+    json_trace_output->erase(json_trace_output->end() - 1);
+
+    BrowserThread::PostTask(BrowserThread::UI, FROM_HERE,
+        base::Bind(&InProcessTraceController::OnEndTracingComplete,
+                   base::Unretained(this)));
+  }
+
+  void OnWatchEventMatched() {
     if (watch_notification_count_ == 0)
       return;
     if (--watch_notification_count_ == 0) {
@@ -118,9 +141,6 @@ class InProcessTraceController : public content::TraceSubscriber {
     message_loop_runner_->Quit();
   }
 
-  // For collecting trace data asynchronously.
-  base::debug::TraceResultBuffer trace_buffer_;
-
   scoped_refptr<content::MessageLoopRunner> message_loop_runner_;
 
   base::OneShotTimer<InProcessTraceController> timer_;