Add builders for tracing event's structural arguments

cc/debug/traced_value.cc

Index: cc/debug/traced_value.cc
diff --git a/cc/debug/traced_value.cc b/cc/debug/traced_value.cc
index 3b506ae7e370aa8153f4ac566cb7dfd1fd1c9ca9..58528f8242b3b250aa6834f46bfe7c323fbf18d8 100644
--- a/cc/debug/traced_value.cc
+++ b/cc/debug/traced_value.cc
@@ -4,6 +4,7 @@
 
 #include "cc/debug/traced_value.h"
 
+#include "base/debug/trace_event_argument.h"
 #include "base/json/json_writer.h"
 #include "base/strings/stringprintf.h"
 #include "base/values.h"
@@ -41,6 +42,46 @@ void TracedValue::MakeDictIntoImplicitSnapshotWithCategory(
   MakeDictIntoImplicitSnapshot(dict, object_name, id);
 }
 
+void TracedValue::AppendIDRef(const void* id, base::debug::TracedValue* state) {
+  state->BeginDictionary();
+  state->SetString("id_ref", base::StringPrintf("%p", id));
+  state->EndDictionary();
+}
+
+void TracedValue::SetIDRef(const void* id,
+                           base::debug::TracedValue* state,
+                           const char* name) {
+  state->BeginDictionary(name);
+  state->SetString("id_ref", base::StringPrintf("%p", id));
+  state->EndDictionary();
+}
+
+void TracedValue::MakeDictIntoImplicitSnapshot(base::debug::TracedValue* dict,
+                                               const char* object_name,
+                                               const void* id) {
+  dict->SetString("id", base::StringPrintf("%s/%p", object_name, id));
+}
+
+void TracedValue::MakeDictIntoImplicitSnapshotWithCategory(
+    const char* category,
+    base::debug::TracedValue* dict,
+    const char* object_name,
+    const void* id) {
+  dict->SetString("cat", category);
+  MakeDictIntoImplicitSnapshot(dict, object_name, id);
+}
+
+void TracedValue::MakeDictIntoImplicitSnapshotWithCategory(
+    const char* category,
+    base::debug::TracedValue* dict,
+    const char* object_base_type_name,
+    const char* object_name,
+    const void* id) {
+  dict->SetString("cat", category);
+  dict->SetString("base_type", object_base_type_name);
+  MakeDictIntoImplicitSnapshot(dict, object_name, id);
+}
+
 scoped_refptr<base::debug::ConvertableToTraceFormat> TracedValue::FromValue(
     base::Value* value) {
   return scoped_refptr<base::debug::ConvertableToTraceFormat>(