Revert 198124 "Add base/android/activity_status.cc"

> Add base/android/activity_status.cc
> 
> This patch adds a small thread-safe wrapper around the Java
> org.chromium.base.ActivityStatus that can be used to listen to activity state
> changes from native code.
> 
> This uses a base::ObserverListThreadSafe to guarantee that listeners can be
> registered on any threads, and that their OnActivityStateChange() method will
> always be called on the thread that created them.
> 
> + Ensure both C++ and Java always use the same constants when it comes to
> ActivityState values.
> 
> TBR=digit@chromium.org
> BUG=233536
> 
> Review URL: https://codereview.chromium.org/14767011

TBR=pliard@chromium.org

Review URL: https://codereview.chromium.org/14596005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@198141 0039d316-1c4b-4281-b951-d872f2087c98

7 files changed, 8 insertions, 363 deletions

diff --git a/base/android/activity_state_list.h b/base/android/activity_state_list.h
deleted file mode 100644
index d2a84dc..0000000
--- a/base/android/activity_state_list.h
+++ /dev/null
@@ -1,16 +0,0 @@
-// Copyright (c) 2013 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.
-
-// This file intentionally does not have header guards, it's included
-// inside a macro to generate enum.
-
-#ifndef DEFINE_ACTIVITY_STATE
-#error "DEFINE_ACTIVITY_STATE should be defined before including this file"
-#endif
-DEFINE_ACTIVITY_STATE(CREATED, 1)
-DEFINE_ACTIVITY_STATE(STARTED, 2)
-DEFINE_ACTIVITY_STATE(RESUMED, 3)
-DEFINE_ACTIVITY_STATE(PAUSED, 4)
-DEFINE_ACTIVITY_STATE(STOPPED, 5)
-DEFINE_ACTIVITY_STATE(DESTROYED, 6)
diff --git a/base/android/activity_status.cc b/base/android/activity_status.cc
deleted file mode 100644
index 4d0be32..0000000
--- a/base/android/activity_status.cc
+++ /dev/null
@@ -1,66 +0,0 @@
-// Copyright 2013 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/activity_status.h"
-
-#include <jni.h>
-
-#include "base/memory/singleton.h"
-#include "jni/ActivityStatus_jni.h"
-
-namespace base {
-namespace android {
-
-ActivityStatus::Listener::Listener(
-    const ActivityStatus::StateChangeCallback& callback)
-    : callback_(callback) {
-  ActivityStatus::GetInstance()->RegisterListener(this);
-}
-
-ActivityStatus::Listener::~Listener() {
-  ActivityStatus::GetInstance()->UnregisterListener(this);
-}
-
-void ActivityStatus::Listener::Notify(ActivityState state) {
-  callback_.Run(state);
-}
-
-// static
-ActivityStatus* ActivityStatus::GetInstance() {
-  return Singleton<ActivityStatus,
-                   LeakySingletonTraits<ActivityStatus> >::get();
-}
-
-static void OnActivityStateChange(JNIEnv* env, jclass clazz, int new_state) {
-  ActivityStatus* activity_status = ActivityStatus::GetInstance();
-  ActivityState activity_state = static_cast<ActivityState>(new_state);
-  activity_status->OnActivityStateChange(activity_state);
-}
-
-bool ActivityStatus::RegisterBindings(JNIEnv* env) {
-  return RegisterNativesImpl(env);
-}
-
-ActivityStatus::ActivityStatus()
-    : observers_(new ObserverListThreadSafe<Listener>()) {
-  Java_ActivityStatus_registerThreadSafeNativeStateListener(
-      base::android::AttachCurrentThread());
-}
-
-ActivityStatus::~ActivityStatus() {}
-
-void ActivityStatus::RegisterListener(Listener* listener) {
-  observers_->AddObserver(listener);
-}
-
-void ActivityStatus::UnregisterListener(Listener* listener) {
-  observers_->RemoveObserver(listener);
-}
-
-void ActivityStatus::OnActivityStateChange(ActivityState new_state) {
-  observers_->Notify(&ActivityStatus::Listener::Notify, new_state);
-}
-
-}  // namespace android
-}  // namespace base
diff --git a/base/android/activity_status.h b/base/android/activity_status.h
deleted file mode 100644
index 554340c..0000000
--- a/base/android/activity_status.h
+++ /dev/null
@@ -1,97 +0,0 @@
-// Copyright 2013 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.
-
-#ifndef BASE_ANDROID_ACTIVITY_STATUS_H_
-#define BASE_ANDROID_ACTIVITY_STATUS_H_
-
-#include <jni.h>
-
-#include "base/android/jni_android.h"
-#include "base/basictypes.h"
-#include "base/memory/ref_counted.h"
-#include "base/memory/singleton.h"
-#include "base/observer_list_threadsafe.h"
-
-namespace base {
-namespace android {
-
-// Define activity state values like ACTIVITY_STATE_CREATED in a
-// way that ensures they're always the same than their Java counterpart.
-enum ActivityState {
-#define DEFINE_ACTIVITY_STATE(x, y) ACTIVITY_STATE_##x = y,
-#include "base/android/activity_state_list.h"
-#undef DEFINE_ACTIVITY_STATE
-};
-
-// A native helper class to listen to state changes of the current
-// Android Activity. This mirrors org.chromium.base.ActivityStatus.
-// any thread.
-//
-// To start listening, create a new instance, passing a callback to a
-// function that takes an ActivityState parameter. To stop listening,
-// simply delete the listener object. The implementation guarantees
-// that the callback will always be called on the thread that created
-// the listener.
-//
-// Example:
-//
-//    void OnActivityStateChange(ActivityState state) {
-//       ...
-//    }
-//
-//    // Start listening.
-//    ActivityStatus::Listener* my_listener =
-//        new ActivityStatus::Listener(base::Bind(&OnActivityStateChange));
-//
-//    ...
-//
-//    // Stop listening.
-//    delete my_listener
-//
-BASE_EXPORT class ActivityStatus {
- public:
-  typedef base::Callback<void(ActivityState)> StateChangeCallback;
-
-  class Listener {
-   public:
-    explicit Listener(const StateChangeCallback& callback);
-    ~Listener();
-
-   private:
-    friend class ActivityStatus;
-
-    void Notify(ActivityState state);
-
-    StateChangeCallback callback_;
-
-    DISALLOW_COPY_AND_ASSIGN(Listener);
-  };
-
-  // NOTE: The Java ActivityStatus is a singleton too.
-  static ActivityStatus* GetInstance();
-
-  // Internal use: must be public to be called from base_jni_registrar.cc
-  static bool RegisterBindings(JNIEnv* env);
-
-  // Internal use only: must be public to be called from JNI and unit tests.
-  void OnActivityStateChange(ActivityState new_state);
-
- private:
-  friend struct DefaultSingletonTraits<ActivityStatus>;
-
-  ActivityStatus();
-  ~ActivityStatus();
-
-  void RegisterListener(Listener* listener);
-  void UnregisterListener(Listener* listener);
-
-  scoped_refptr<ObserverListThreadSafe<Listener> > observers_;
-
-  DISALLOW_COPY_AND_ASSIGN(ActivityStatus);
-};
-
-}  // namespace android
-}  // namespace base
-
-#endif  // BASE_ANDROID_ACTIVITY_STATUS_H_
diff --git a/base/android/activity_status_unittest.cc b/base/android/activity_status_unittest.cc
deleted file mode 100644
index aa6a69f..0000000
--- a/base/android/activity_status_unittest.cc
+++ /dev/null
@@ -1,129 +0,0 @@
-// Copyright 2013 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/activity_status.h"
-#include "base/bind.h"
-#include "base/callback_forward.h"
-#include "base/logging.h"
-#include "base/memory/scoped_ptr.h"
-#include "base/message_loop/message_loop_proxy.h"
-#include "base/run_loop.h"
-#include "base/synchronization/waitable_event.h"
-#include "base/threading/thread.h"
-#include "testing/gtest/include/gtest/gtest.h"
-
-namespace base {
-namespace android {
-
-namespace {
-
-using base::android::ScopedJavaLocalRef;
-
-// An invalid ActivityState value.
-const ActivityState kInvalidActivityState = static_cast<ActivityState>(100);
-
-// Used to generate a callback that stores the new state at a given location.
-void StoreStateTo(ActivityState* target, ActivityState state) {
-  *target = state;
-}
-
-void RunTasksUntilIdle() {
-  RunLoop run_loop;
-  run_loop.RunUntilIdle();
-}
-
-// Shared state for the multi-threaded test.
-// This uses a thread to register for events and listen to them, while state
-// changes are forced on the main thread.
-class MultiThreadedTest {
- public:
-  MultiThreadedTest()
-      : activity_status_(ActivityStatus::GetInstance()),
-        state_(kInvalidActivityState),
-        event_(false, false),
-        thread_("ActivityStatusTest thread"),
-        main_(),
-        listener_(NULL) {
-  }
-
-  void Run() {
-    // Start the thread and tell it to register for events.
-    thread_.Start();
-    thread_.message_loop()
-        ->PostTask(FROM_HERE,
-                   base::Bind(&MultiThreadedTest::RegisterThreadForEvents,
-                              base::Unretained(this)));
-
-    // Wait for its completion.
-    event_.Wait();
-
-    // Change state, then wait for the thread to modify state.
-    activity_status_->OnActivityStateChange(ACTIVITY_STATE_CREATED);
-    event_.Wait();
-    EXPECT_EQ(ACTIVITY_STATE_CREATED, state_);
-
-    // Again
-    activity_status_->OnActivityStateChange(ACTIVITY_STATE_DESTROYED);
-    event_.Wait();
-    EXPECT_EQ(ACTIVITY_STATE_DESTROYED, state_);
-  }
-
- private:
-  void ExpectOnThread() {
-    EXPECT_EQ(thread_.message_loop(), base::MessageLoop::current());
-  }
-
-  void RegisterThreadForEvents() {
-    ExpectOnThread();
-    listener_.reset(new ActivityStatus::Listener(base::Bind(
-        &MultiThreadedTest::StoreStateAndSignal, base::Unretained(this))));
-    EXPECT_TRUE(listener_.get());
-    event_.Signal();
-  }
-
-  void StoreStateAndSignal(ActivityState state) {
-    ExpectOnThread();
-    state_ = state;
-    event_.Signal();
-  }
-
-  ActivityStatus* const activity_status_;
-  ActivityState state_;
-  base::WaitableEvent event_;
-  base::Thread thread_;
-  base::MessageLoop main_;
-  scoped_ptr<ActivityStatus::Listener> listener_;
-};
-
-}  // namespace
-
-TEST(ActivityStatusTest, SingleThread) {
-  MessageLoop message_loop;
-
-  ActivityState result = kInvalidActivityState;
-
-  // Create a new listener that stores the new state into |result| on every
-  // state change.
-  ActivityStatus::Listener listener(
-      base::Bind(&StoreStateTo, base::Unretained(&result)));
-
-  EXPECT_EQ(kInvalidActivityState, result);
-
-  ActivityStatus* const activity_status = ActivityStatus::GetInstance();
-  activity_status->OnActivityStateChange(ACTIVITY_STATE_CREATED);
-  RunTasksUntilIdle();
-  EXPECT_EQ(ACTIVITY_STATE_CREATED, result);
-
-  activity_status->OnActivityStateChange(ACTIVITY_STATE_DESTROYED);
-  RunTasksUntilIdle();
-  EXPECT_EQ(ACTIVITY_STATE_DESTROYED, result);
-}
-
-TEST(ActivityStatusTest, TwoThreads) {
-  MultiThreadedTest test;
-  test.Run();
-}
-
-}  // namespace android
-}  // namespace base
diff --git a/base/android/base_jni_registrar.cc b/base/android/base_jni_registrar.cc
index 606ab38..882938b 100644
--- a/base/android/base_jni_registrar.cc
+++ b/base/android/base_jni_registrar.cc
@@ -4,7 +4,7 @@
 
 #include "base/android/base_jni_registrar.h"
 
-#include "base/android/activity_status.h"
+#include "base/basictypes.h"
 #include "base/android/build_info.h"
 #include "base/android/cpu_features.h"
 #include "base/android/important_file_writer_android.h"
@@ -13,7 +13,6 @@
 #include "base/android/path_service_android.h"
 #include "base/android/path_utils.h"
 #include "base/android/thread_utils.h"
-#include "base/basictypes.h"
 #include "base/debug/trace_event.h"
 #include "base/message_pump_android.h"
 #include "base/power_monitor/power_monitor_android.h"
@@ -22,7 +21,6 @@ namespace base {
 namespace android {
 
 static RegistrationMethod kBaseRegisteredMethods[] = {
-  { "ActivityStatus", base::android::ActivityStatus::RegisterBindings },
   { "BuildInfo", base::android::BuildInfo::RegisterBindings },
   { "CpuFeatures", base::android::RegisterCpuFeatures },
   { "ImportantFileWriterAndroid",
diff --git a/base/android/java/src/org/chromium/base/ActivityState.template b/base/android/java/src/org/chromium/base/ActivityState.template
deleted file mode 100644
index adf990a..0000000
--- a/base/android/java/src/org/chromium/base/ActivityState.template
+++ /dev/null
@@ -1,14 +0,0 @@
-// Copyright (c) 2013 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.
-
-package org.chromium.base;
-
-// A simple auto-generated interface used to list the various
-// states of an activity as used by both org.chromium.base.ActivityStatus
-// and base/android/activity_status.h
-interface ActivityState {
-#define DEFINE_ACTIVITY_STATE(x,y) public final int x = y;
-#include "base/android/activity_state_list.h"
-#undef DEFINE_ACTIVITY_STATE
-}
diff --git a/base/android/java/src/org/chromium/base/ActivityStatus.java b/base/android/java/src/org/chromium/base/ActivityStatus.java
index 4747234..7d0ee94 100644
--- a/base/android/java/src/org/chromium/base/ActivityStatus.java
+++ b/base/android/java/src/org/chromium/base/ActivityStatus.java
@@ -5,25 +5,20 @@
 package org.chromium.base;
 
 import android.app.Activity;
-import android.os.Handler;
 import android.os.Looper;
 
 /**
- * Provides information about the current activity's status, and a way
- * to register / unregister listeners for state changes.
+ * Provides information about the parent activity's status.
  */
-@JNINamespace("base::android")
 public class ActivityStatus {
 
     // Constants matching activity states reported to StateListener.onStateChange
-    // As an implementation detail, these are now defined in the auto-generated
-    // ActivityState interface, to be shared with C++.
-    public static final int CREATED = ActivityState.CREATED;
-    public static final int STARTED = ActivityState.STARTED;
-    public static final int RESUMED = ActivityState.RESUMED;
-    public static final int PAUSED = ActivityState.PAUSED;
-    public static final int STOPPED = ActivityState.STOPPED;
-    public static final int DESTROYED = ActivityState.DESTROYED;
+    public static final int CREATED = 1;
+    public static final int STARTED = 2;
+    public static final int RESUMED = 3;
+    public static final int PAUSED = 4;
+    public static final int STOPPED = 5;
+    public static final int DESTROYED = 6;
 
     // Current main activity, or null if none.
     private static Activity sActivity;
@@ -107,30 +102,4 @@ public class ActivityStatus {
     public static void unregisterStateListener(StateListener listener) {
         sStateListeners.removeObserver(listener);
     }
-
-    /**
-     * Registers the single thread-safe native activity status listener.
-     * This handles the case where the caller is not on the main thread.
-     * Note that this is used by a leaky singleton object from the native
-     * side, hence lifecycle management is greatly simplified.
-     */
-    @CalledByNative
-    private static void registerThreadSafeNativeStateListener() {
-        ThreadUtils.runOnUiThread(new Runnable () {
-            @Override
-            public void run() {
-                // Register a new listener that calls nativeOnActivityStateChange.
-                sStateListeners.addObserver(new StateListener() {
-                    @Override
-                    public void onActivityStateChange(int newState) {
-                        nativeOnActivityStateChange(newState);
-                    }
-                });
-            }
-        });
-    }
-
-    // Called to notify the native side of state changes.
-    // IMPORTANT: This is always called on the main thread!
-    private static native void nativeOnActivityStateChange(int newState);
 }