android: Add the target to toplevel Looper events in tracing,

base/android/trace_event_binding.cc

 // Copyright 2014 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/android/trace_event_binding.h"
 
 #include <jni.h>
 
 #include <set>
 
@@ skipping 103 matching lines @@
                 const JavaParamRef<jstring>& jarg) {
   TraceEventDataConverter converter(env, jname, jarg);
   if (converter.arg()) {
     TRACE_EVENT_COPY_END1(kJavaCategory, converter.name(),
                      converter.arg_name(), converter.arg());
   } else {
     TRACE_EVENT_COPY_END0(kJavaCategory, converter.name());
   }
 }
 
-static void BeginToplevel(JNIEnv* env, const JavaParamRef<jclass>& clazz) {
-  TRACE_EVENT_BEGIN0(kToplevelCategory, kLooperDispatchMessage);
+static void BeginToplevel(JNIEnv* env,
+                          const JavaParamRef<jclass>& clazz,
+                          const JavaParamRef<jstring>& jtarget) {
+  std::string target = ConvertJavaStringToUTF8(env, jtarget);
+  TRACE_EVENT_BEGIN1(kToplevelCategory, kLooperDispatchMessage, "target",
+                     target);
 }
 
 static void EndToplevel(JNIEnv* env, const JavaParamRef<jclass>& clazz) {
   TRACE_EVENT_END0(kToplevelCategory, kLooperDispatchMessage);
 }
 
 static void StartAsync(JNIEnv* env,
                        const JavaParamRef<jclass>& clazz,
                        const JavaParamRef<jstring>& jname,
                        jlong jid) {
   TraceEventDataConverter converter(env, jname, nullptr);
   TRACE_EVENT_COPY_ASYNC_BEGIN0(kJavaCategory, converter.name(), jid);
 }
 
 static void FinishAsync(JNIEnv* env,
                         const JavaParamRef<jclass>& clazz,
                         const JavaParamRef<jstring>& jname,
                         jlong jid) {
   TraceEventDataConverter converter(env, jname, nullptr);
   TRACE_EVENT_COPY_ASYNC_END0(kJavaCategory, converter.name(), jid);
 }
 
 bool RegisterTraceEvent(JNIEnv* env) {
   return RegisterNativesImpl(env);
 }
 
 }  // namespace android
 }  // namespace base