Add builders for tracing event's structural arguments

cc/scheduler/scheduler_unittest.cc

Index: cc/scheduler/scheduler_unittest.cc
diff --git a/cc/scheduler/scheduler_unittest.cc b/cc/scheduler/scheduler_unittest.cc
index aa61af73e884bde064647b08281406ca41df2511..f416cec008fabc87c04786e619bc2b1bb0ffea5d 100644
--- a/cc/scheduler/scheduler_unittest.cc
+++ b/cc/scheduler/scheduler_unittest.cc
@@ -6,6 +6,7 @@
 #include <string>
 #include <vector>
 
+#include "base/debug/trace_event.h"
 #include "base/logging.h"
 #include "base/memory/scoped_vector.h"
 #include "base/message_loop/message_loop.h"
@@ -110,7 +111,7 @@ class FakeSchedulerClient : public SchedulerClient {
   int num_draws() const { return num_draws_; }
   int num_actions_() const { return static_cast<int>(actions_.size()); }
   const char* Action(int i) const { return actions_[i]; }
-  base::Value& StateForAction(int i) const { return *states_[i]; }
+  std::string StateForAction(int i) const { return states_[i]->ToString(); }
   base::TimeTicks posted_begin_impl_frame_deadline() const {
     return posted_begin_impl_frame_deadline_;
   }
@@ -147,24 +148,24 @@ class FakeSchedulerClient : public SchedulerClient {
   // SchedulerClient implementation.
   virtual void SetNeedsBeginFrame(bool enable) OVERRIDE {
     actions_.push_back("SetNeedsBeginFrame");
-    states_.push_back(scheduler_->AsValue().release());
+    states_.push_back(scheduler_->AsValue());
     needs_begin_frame_ = enable;
   }
   virtual void WillBeginImplFrame(const BeginFrameArgs& args) OVERRIDE {
     actions_.push_back("WillBeginImplFrame");
-    states_.push_back(scheduler_->AsValue().release());
+    states_.push_back(scheduler_->AsValue());
   }
   virtual void ScheduledActionSendBeginMainFrame() OVERRIDE {
     actions_.push_back("ScheduledActionSendBeginMainFrame");
-    states_.push_back(scheduler_->AsValue().release());
+    states_.push_back(scheduler_->AsValue());
   }
   virtual void ScheduledActionAnimate() OVERRIDE {
     actions_.push_back("ScheduledActionAnimate");
-    states_.push_back(scheduler_->AsValue().release());
+    states_.push_back(scheduler_->AsValue());
   }
   virtual DrawResult ScheduledActionDrawAndSwapIfPossible() OVERRIDE {
     actions_.push_back("ScheduledActionDrawAndSwapIfPossible");
-    states_.push_back(scheduler_->AsValue().release());
+    states_.push_back(scheduler_->AsValue());
     num_draws_++;
     DrawResult result =
         draw_will_happen_ ? DRAW_SUCCESS : DRAW_ABORTED_CHECKERBOARD_ANIMATIONS;
@@ -186,30 +187,30 @@ class FakeSchedulerClient : public SchedulerClient {
   }
   virtual DrawResult ScheduledActionDrawAndSwapForced() OVERRIDE {
     actions_.push_back("ScheduledActionDrawAndSwapForced");
-    states_.push_back(scheduler_->AsValue().release());
+    states_.push_back(scheduler_->AsValue());
     return DRAW_SUCCESS;
   }
   virtual void ScheduledActionCommit() OVERRIDE {
     actions_.push_back("ScheduledActionCommit");
-    states_.push_back(scheduler_->AsValue().release());
+    states_.push_back(scheduler_->AsValue());
   }
   virtual void ScheduledActionUpdateVisibleTiles() OVERRIDE {
     actions_.push_back("ScheduledActionUpdateVisibleTiles");
-    states_.push_back(scheduler_->AsValue().release());
+    states_.push_back(scheduler_->AsValue());
     if (redraw_will_happen_if_update_visible_tiles_happens_)
       scheduler_->SetNeedsRedraw();
   }
   virtual void ScheduledActionActivateSyncTree() OVERRIDE {
     actions_.push_back("ScheduledActionActivateSyncTree");
-    states_.push_back(scheduler_->AsValue().release());
+    states_.push_back(scheduler_->AsValue());
   }
   virtual void ScheduledActionBeginOutputSurfaceCreation() OVERRIDE {
     actions_.push_back("ScheduledActionBeginOutputSurfaceCreation");
-    states_.push_back(scheduler_->AsValue().release());
+    states_.push_back(scheduler_->AsValue());
   }
   virtual void ScheduledActionManageTiles() OVERRIDE {
     actions_.push_back("ScheduledActionManageTiles");
-    states_.push_back(scheduler_->AsValue().release());
+    states_.push_back(scheduler_->AsValue());
   }
   virtual void DidAnticipatedDrawTimeChange(base::TimeTicks) OVERRIDE {
     if (log_anticipated_draw_time_change_)
@@ -238,7 +239,7 @@ class FakeSchedulerClient : public SchedulerClient {
   bool redraw_will_happen_if_update_visible_tiles_happens_;
   base::TimeTicks posted_begin_impl_frame_deadline_;
   std::vector<const char*> actions_;
-  ScopedVector<base::Value> states_;
+  std::vector<scoped_refptr<base::debug::ConvertableToTraceFormat> > states_;
   scoped_ptr<TestScheduler> scheduler_;
   scoped_refptr<OrderedSimpleTaskRunner> task_runner_;
 };
@@ -1167,7 +1168,7 @@ TEST(SchedulerTest, PollForCommitCompletion) {
   for (int i = 0; i < 3; ++i) {
     EXPECT_EQ((frame_args.interval * 2).InMicroseconds(),
               client.task_runner().NextPendingTaskDelay().InMicroseconds())
-        << *scheduler->AsValue();
+        << scheduler->AsValue()->ToString();
     client.task_runner().RunPendingTasks();
     EXPECT_GT(client.num_actions_(), actions_so_far);
     EXPECT_STREQ(client.Action(client.num_actions_() - 1),
@@ -1180,7 +1181,7 @@ TEST(SchedulerTest, PollForCommitCompletion) {
   for (int i = 0; i < 3; ++i) {
     EXPECT_EQ((frame_args.interval * 2).InMicroseconds(),
               client.task_runner().NextPendingTaskDelay().InMicroseconds())
-        << *scheduler->AsValue();
+        << scheduler->AsValue()->ToString();
     client.task_runner().RunPendingTasks();
     EXPECT_GT(client.num_actions_(), actions_so_far);
     EXPECT_STREQ(client.Action(client.num_actions_() - 1),