Fix Java thread names on Android.

To get correct thread names in Chrome tracing, it's necessary to register
threads with the base::ThreadIdNameManager and set the thread name.

BUG=873377

Change-Id: Icb8d68f941f95f65c53ae19b16e05f0d85c9bfbd
Reviewed-on: https://chromium-review.googlesource.com/1192589Reviewed-by: Yaron Friedman <yfriedman@chromium.org>
Commit-Queue: Victor Miura <vmiura@chromium.org>
Cr-Commit-Position: refs/heads/master@{#587242}

base/android/java_handler_thread.cc

@@ -12,6 +12,7 @@
 #include "base/run_loop.h"
 #include "base/synchronization/waitable_event.h"
 #include "base/threading/platform_thread_internal_posix.h"
+#include "base/threading/thread_id_name_manager.h"
 #include "base/threading/thread_restrictions.h"
 #include "jni/JavaHandlerThread_jni.h"
 
@@ -23,14 +24,17 @@ namespace android {
 
 JavaHandlerThread::JavaHandlerThread(const char* name,
                                      base::ThreadPriority priority)
-    : JavaHandlerThread(Java_JavaHandlerThread_create(
-          AttachCurrentThread(),
-          ConvertUTF8ToJavaString(AttachCurrentThread(), name),
-          base::internal::ThreadPriorityToNiceValue(priority))) {}
+    : JavaHandlerThread(
+          name,
+          Java_JavaHandlerThread_create(
+              AttachCurrentThread(),
+              ConvertUTF8ToJavaString(AttachCurrentThread(), name),
+              base::internal::ThreadPriorityToNiceValue(priority))) {}
 
 JavaHandlerThread::JavaHandlerThread(
+    const char* name,
     const base::android::ScopedJavaLocalRef<jobject>& obj)
-    : java_thread_(obj) {}
+    : name_(name), java_thread_(obj) {}
 
 JavaHandlerThread::~JavaHandlerThread() {
   JNIEnv* env = base::android::AttachCurrentThread();
@@ -77,6 +81,13 @@ void JavaHandlerThread::Stop() {
 void JavaHandlerThread::InitializeThread(JNIEnv* env,
                                          const JavaParamRef<jobject>& obj,
                                          jlong event) {
+  base::ThreadIdNameManager::GetInstance()->RegisterThread(
+      base::PlatformThread::CurrentHandle().platform_handle(),
+      base::PlatformThread::CurrentId());
+
+  if (name_)
+    PlatformThread::SetName(name_);
+
   // TYPE_JAVA to get the Android java style message loop.
   message_loop_ =
       std::make_unique<MessageLoopForUI>(base::MessageLoop::TYPE_JAVA);
@@ -88,7 +99,12 @@ void JavaHandlerThread::OnLooperStopped(JNIEnv* env,
                                         const JavaParamRef<jobject>& obj) {
   DCHECK(task_runner()->BelongsToCurrentThread());
   message_loop_.reset();
+
   CleanUp();
+
+  base::ThreadIdNameManager::GetInstance()->RemoveName(
+      base::PlatformThread::CurrentHandle().platform_handle(),
+      base::PlatformThread::CurrentId());
 }
 
 void JavaHandlerThread::StopMessageLoopForTesting() {

base/android/java_handler_thread.h

@@ -33,6 +33,7 @@ class BASE_EXPORT JavaHandlerThread {
   // Wrap and connect to an existing JavaHandlerThread.
   // |obj| is an instance of JavaHandlerThread.
   explicit JavaHandlerThread(
+      const char* name,
       const base::android::ScopedJavaLocalRef<jobject>& obj);
   virtual ~JavaHandlerThread();
 
@@ -86,6 +87,7 @@ class BASE_EXPORT JavaHandlerThread {
   void StopOnThread();
   void QuitThreadSafely();
 
+  const char* name_;
   ScopedJavaGlobalRef<jobject> java_thread_;
 };
 

base/test/android/java_handler_thread_helpers.cc

@@ -15,8 +15,8 @@ namespace android {
 // static
 std::unique_ptr<JavaHandlerThread> JavaHandlerThreadHelpers::CreateJavaFirst() {
   return std::make_unique<JavaHandlerThread>(
-      Java_JavaHandlerThreadHelpers_testAndGetJavaHandlerThread(
-          base::android::AttachCurrentThread()));
+      nullptr, Java_JavaHandlerThreadHelpers_testAndGetJavaHandlerThread(
+                   base::android::AttachCurrentThread()));
 }
 
 // static

content/browser/android/launcher_thread.cc

@@ -18,8 +18,9 @@ base::MessageLoop* LauncherThread::GetMessageLoop() {
 }
 
 LauncherThread::LauncherThread()
-    : java_handler_thread_(Java_LauncherThread_getHandlerThread(
-          base::android::AttachCurrentThread())) {
+    : java_handler_thread_(nullptr,
+                           Java_LauncherThread_getHandlerThread(
+                               base::android::AttachCurrentThread())) {
   java_handler_thread_.Start();
 }