Update tracing framework to optionally use a ringbuffer.

base/debug/trace_event_unittest.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/debug/trace_event_unittest.h"
 
 #include <cstdlib>
 
 #include "base/bind.h"
 #include "base/command_line.h"
@@ skipping 1513 matching lines @@
   trace_log->SetDisabled();
 }
 
 TEST_F(TraceEventTestFixture, TraceOptionsParsing) {
   ManualTestSetUp();
 
   EXPECT_EQ(TraceLog::RECORD_UNTIL_FULL, TraceLog::TraceOptionsFromString(""));
 
   EXPECT_EQ(TraceLog::RECORD_UNTIL_FULL,
             TraceLog::TraceOptionsFromString("record-until-full"));
+  EXPECT_EQ(TraceLog::RECORD_CONTINUOUSLY,
+            TraceLog::TraceOptionsFromString("record-continuously"));
 }
 
 TEST_F(TraceEventTestFixture, TraceSampling) {
   ManualTestSetUp();
 
   event_watch_notification_ = 0;
   TraceLog::GetInstance()->SetEnabled(
       std::string("*"),
       TraceLog::Options(TraceLog::RECORD_UNTIL_FULL |
                         TraceLog::ENABLE_SAMPLING));
@@ skipping 55 matching lines @@
   TraceLog::GetInstance()->SetEventCallback(Callback);
   TRACE_EVENT_INSTANT0("all", "event1");
   TRACE_EVENT_INSTANT0("all", "event2");
   TraceLog::GetInstance()->SetEventCallback(NULL);
   TRACE_EVENT_INSTANT0("all", "after callback removed");
   EXPECT_EQ(2u, collected_events_.size());
   EXPECT_EQ("event1", collected_events_[0]);
   EXPECT_EQ("event2", collected_events_[1]);
 }
 
+// TODO(dsinclair): Continuous Tracing unit test.
+
 }  // namespace debug
 }  // namespace base