Reland "Make Interaction Media Features MQ dynamic on Android"

This is a reland of 1bdb8833 without
changes. 

Original CL was reverted due to a bug in how chromium 
generates JNI bindings with native functions. It is fixed by 
https://codereview.chromium.org/2966163006/.

Original change's description:
> Make Interaction Media Features MQ dynamic on Android
> 
> With detachable form factors such as Asus Transformer
> it is important to make sure the interaction media
> features are updated whenever the keyboard/trackpad combo is
> detached. This will allow content author to react to
> media query changes to adapt the user interface to
> better suit the new interaction method (often touch vs
> trackpad). The patch also handles any input changes e.g.
> USB connected mouse.
> 
> The patch uses the facility landed in previous OSes and
> add a bit of Java code to listen the changes of inputs
> through the InputDeviceListener mechanism.
> 
> BUG=442418
> 
> Change-Id: I5c18ce4df8e6da927eede5a24f40aac10ecf1974
> Reviewed-on: https://chromium-review.googlesource.com/553457
> Reviewed-by: Sadrul Chowdhury <sadrul@chromium.org>
> Reviewed-by: Andrew Grieve <agrieve@chromium.org>
> Reviewed-by: Bo Liu <boliu@chromium.org>
> Commit-Queue: Alexis Menard <alexis.menard@intel.com>
> Cr-Commit-Position: refs/heads/master@{#484641}


TBR=agrieve@chromium.org, alexis.menard@intel.com, boliu@chromium.org, sadrul@chromium.org

Bug: 442418
Change-Id: I5dca047c566625fa2f976d3311899f9a3a23f44e
Reviewed-on: https://chromium-review.googlesource.com/563478Reviewed-by: Alexis Menard <alexis.menard@intel.com>
Commit-Queue: Alexis Menard <alexis.menard@intel.com>
Cr-Commit-Position: refs/heads/master@{#484981}

chrome/BUILD.gn

@@ -1767,6 +1767,7 @@ if (is_android) {
       deps += [
         "//device/gamepad",
         "//device/sensors",
+        "//ui/events/devices",
       ]
     }
   }

content/browser/renderer_host/input/input_device_change_observer.cc

@@ -4,12 +4,15 @@
 
 #include "content/browser/renderer_host/input/input_device_change_observer.h"
 #include "base/trace_event/trace_event.h"
+#include "build/build_config.h"
 #include "content/public/common/web_preferences.h"
 
 #if defined(OS_WIN)
 #include "ui/events/devices/input_device_observer_win.h"
 #elif defined(OS_LINUX)
 #include "ui/events/devices/input_device_manager.h"
+#elif defined(OS_ANDROID)
+#include "ui/events/devices/input_device_observer_android.h"
 #endif
 
 namespace content {
@@ -20,6 +23,8 @@ InputDeviceChangeObserver::InputDeviceChangeObserver(RenderViewHost* rvh) {
   ui::InputDeviceObserverWin::GetInstance()->AddObserver(this);
 #elif defined(OS_LINUX)
   ui::InputDeviceManager::GetInstance()->AddObserver(this);
+#elif defined(OS_ANDROID)
+  ui::InputDeviceObserverAndroid::GetInstance()->AddObserver(this);
 #endif
 }
 
@@ -28,6 +33,8 @@ InputDeviceChangeObserver::~InputDeviceChangeObserver() {
   ui::InputDeviceObserverWin::GetInstance()->RemoveObserver(this);
 #elif defined(OS_LINUX)
   ui::InputDeviceManager::GetInstance()->RemoveObserver(this);
+#elif defined(OS_ANDROID)
+  ui::InputDeviceObserverAndroid::GetInstance()->RemoveObserver(this);
 #endif
   render_view_host_ = nullptr;
 }

content/browser/renderer_host/input/interaction_mq_dynamic_browsertest.cc

@@ -4,6 +4,7 @@
 
 #include "base/macros.h"
 #include "base/strings/utf_string_conversions.h"
+#include "build/build_config.h"
 #include "content/browser/renderer_host/render_view_host_impl.h"
 #include "content/public/browser/web_contents.h"
 #include "content/public/test/browser_test_utils.h"
@@ -25,7 +26,7 @@ class InteractionMediaQueriesDynamicTest : public ContentBrowserTest {
 
 }  //  namespace
 
-#if defined(OS_WIN) || defined(OS_LINUX)
+#if defined(OS_WIN) || defined(OS_LINUX) || defined(OS_ANDROID)
 IN_PROC_BROWSER_TEST_F(InteractionMediaQueriesDynamicTest,
                        PointerMediaQueriesDynamic) {
   GURL test_url = GetTestUrl("", "interaction-mq-dynamic.html");

ui/android/BUILD.gn

@@ -66,6 +66,7 @@ component("android") {
     "//ui/base",
     "//ui/display",
     "//ui/events",
+    "//ui/events/devices",
     "//ui/gfx",
     "//ui/gfx/geometry",
     "//url",
@@ -213,6 +214,7 @@ android_library("ui_full_java") {
     "java/src/org/chromium/ui/display/DisplaySwitches.java",
     "java/src/org/chromium/ui/display/PhysicalDisplayAndroid.java",
     "java/src/org/chromium/ui/display/VirtualDisplayAndroid.java",
+    "java/src/org/chromium/ui/events/devices/InputDeviceObserver.java",
     "java/src/org/chromium/ui/gfx/BitmapHelper.java",
     "java/src/org/chromium/ui/gfx/ViewConfigurationHelper.java",
     "java/src/org/chromium/ui/gl/SurfaceTextureListener.java",

ui/android/java/src/org/chromium/ui/events/devices/InputDeviceObserver.java

+// Copyright 2017 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.ui.events.devices;
+
+import android.content.Context;
+import android.hardware.input.InputManager;
+import android.hardware.input.InputManager.InputDeviceListener;
+
+import org.chromium.base.ContextUtils;
+import org.chromium.base.ThreadUtils;
+import org.chromium.base.annotations.CalledByNative;
+import org.chromium.base.annotations.JNINamespace;
+
+/**
+ * A singleton that helps detecting changes in input devices through the interface
+ * {@link InputDeviceObserver}.
+ */
+@JNINamespace("ui")
+public class InputDeviceObserver implements InputDeviceListener {
+    private static final InputDeviceObserver INSTANCE = new InputDeviceObserver();
+
+    /**
+     * Notifies the InputDeviceObserver that an observer is attached and it
+     * should prepare itself for listening input changes.
+     */
+    @CalledByNative
+    public static void addObserver() {
+        assert ThreadUtils.runningOnUiThread();
+        INSTANCE.attachObserver();
+    }
+
+    /**
+     * Notifies the InputDeviceObserver that an observer has been removed.
+     */
+    @CalledByNative
+    public static void removeObserver() {
+        assert ThreadUtils.runningOnUiThread();
+        INSTANCE.detachObserver();
+    }
+
+    private InputManager mInputManager;
+    private InputDeviceListener mInputDeviceListener;
+    private int mObserversCounter;
+
+    // Override InputDeviceListener methods
+    @Override
+    public void onInputDeviceChanged(int deviceId) {
+        nativeInputConfigurationChanged();
+    }
+
+    @Override
+    public void onInputDeviceRemoved(int deviceId) {
+        nativeInputConfigurationChanged();
+    }
+
+    @Override
+    public void onInputDeviceAdded(int deviceId) {
+        nativeInputConfigurationChanged();
+    }
+
+    private void attachObserver() {
+        if (mObserversCounter++ == 0) {
+            Context context = ContextUtils.getApplicationContext();
+            mInputManager = (InputManager) context.getSystemService(Context.INPUT_SERVICE);
+            // Register an input device listener.
+            mInputManager.registerInputDeviceListener(this, null);
+        }
+    }
+
+    private void detachObserver() {
+        assert mObserversCounter > 0;
+        if (--mObserversCounter == 0) {
+            mInputManager.unregisterInputDeviceListener(this);
+            mInputManager = null;
+        }
+    }
+
+    private native void nativeInputConfigurationChanged();
+}
\ No newline at end of file

ui/base/BUILD.gn

@@ -367,7 +367,6 @@ component("base") {
     sources += [ "touch/touch_device_win.cc" ]
   } else if (is_android) {
     sources += [ "touch/touch_device_android.cc" ]
-    sources -= [ "touch/touch_device_util.cc" ]
   } else if (is_ios) {
     sources += [ "touch/touch_device_ios.cc" ]
   } else if (is_linux) {

ui/base/touch/touch_device_android.cc

@@ -20,7 +20,7 @@ int MaxTouchPoints() {
   return Java_TouchDevice_maxTouchPoints(AttachCurrentThread());
 }
 
-std::pair<int, int> GetAvailablePointerAndHoverTypes() {
+std::pair<int, int> AvailablePointerAndHoverTypes() {
   JNIEnv* env = AttachCurrentThread();
   std::vector<int> pointer_and_hover_types;
   base::android::JavaIntArrayToIntVector(
@@ -30,6 +30,14 @@ std::pair<int, int> GetAvailablePointerAndHoverTypes() {
   return std::make_pair(pointer_and_hover_types[0], pointer_and_hover_types[1]);
 }
 
+int GetAvailableHoverTypes() {
+  return AvailablePointerAndHoverTypes().second;
+}
+
+int GetAvailablePointerTypes() {
+  return AvailablePointerAndHoverTypes().first;
+}
+
 PointerType GetPrimaryPointerType(int available_pointer_types) {
   if (available_pointer_types & POINTER_TYPE_COARSE)
     return POINTER_TYPE_COARSE;

ui/events/devices/BUILD.gn

@@ -2,6 +2,11 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
+if (is_android) {
+  import("//build/config/android/config.gni")
+  import("//build/config/android/rules.gni")
+}
+
 component("devices") {
   sources = [
     "device_data_manager.cc",
@@ -15,6 +20,8 @@ component("devices") {
     "input_device_event_observer.h",
     "input_device_manager.cc",
     "input_device_manager.h",
+    "input_device_observer_android.cc",
+    "input_device_observer_android.h",
     "input_device_observer_win.cc",
     "input_device_observer_win.h",
     "stylus_state.h",
@@ -35,4 +42,17 @@ component("devices") {
     "//ui/display/types",
     "//ui/gfx/geometry",
   ]
+
+  if (is_android) {
+    deps += [ ":ui_events_devices_jni_headers" ]
+  }
+}
+
+if (is_android) {
+  generate_jni("ui_events_devices_jni_headers") {
+    sources = [
+      "../../android/java/src/org/chromium/ui/events/devices/InputDeviceObserver.java",
+    ]
+    jni_package = "events/devices"
+  }
 }

ui/events/devices/DEPS

+specific_include_rules = {
+  "input_device_observer_android.cc": [
+    "+jni",
+  ],
+}

ui/events/devices/input_device_observer_android.cc

+// Copyright 2017 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 "ui/events/devices/input_device_observer_android.h"
+
+#include "base/memory/singleton.h"
+#include "jni/InputDeviceObserver_jni.h"
+
+using base::android::AttachCurrentThread;
+using base::android::JavaParamRef;
+
+// This macro provides the implementation for the observer notification methods.
+#define NOTIFY_OBSERVERS(method_decl, observer_call)           \
+  void InputDeviceObserverAndroid::method_decl {               \
+    for (ui::InputDeviceEventObserver & observer : observers_) \
+      observer.observer_call;                                  \
+  }
+
+namespace ui {
+
+bool InputDeviceObserverAndroid::RegisterInputDeviceObserver(JNIEnv* env) {
+  return RegisterNativesImpl(env);
+}
+
+InputDeviceObserverAndroid::InputDeviceObserverAndroid() {}
+
+InputDeviceObserverAndroid::~InputDeviceObserverAndroid() {}
+
+InputDeviceObserverAndroid* InputDeviceObserverAndroid::GetInstance() {
+  return base::Singleton<
+      InputDeviceObserverAndroid,
+      base::LeakySingletonTraits<InputDeviceObserverAndroid>>::get();
+}
+
+void InputDeviceObserverAndroid::AddObserver(
+    ui::InputDeviceEventObserver* observer) {
+  observers_.AddObserver(observer);
+  JNIEnv* env = AttachCurrentThread();
+  Java_InputDeviceObserver_addObserver(env);
+}
+
+void InputDeviceObserverAndroid::RemoveObserver(
+    ui::InputDeviceEventObserver* observer) {
+  observers_.RemoveObserver(observer);
+  JNIEnv* env = AttachCurrentThread();
+  Java_InputDeviceObserver_removeObserver(env);
+}
+
+static void InputConfigurationChanged(JNIEnv* env,
+                                      const JavaParamRef<jobject>& obj) {
+  InputDeviceObserverAndroid::GetInstance()
+      ->NotifyObserversTouchpadDeviceConfigurationChanged();
+  InputDeviceObserverAndroid::GetInstance()
+      ->NotifyObserversKeyboardDeviceConfigurationChanged();
+  InputDeviceObserverAndroid::GetInstance()
+      ->NotifyObserversMouseDeviceConfigurationChanged();
+}
+
+NOTIFY_OBSERVERS(NotifyObserversMouseDeviceConfigurationChanged(),
+                 OnMouseDeviceConfigurationChanged());
+NOTIFY_OBSERVERS(NotifyObserversTouchpadDeviceConfigurationChanged(),
+                 OnTouchpadDeviceConfigurationChanged());
+NOTIFY_OBSERVERS(NotifyObserversKeyboardDeviceConfigurationChanged(),
+                 OnKeyboardDeviceConfigurationChanged());
+
+}  // namespace ui
\ No newline at end of file

ui/events/devices/input_device_observer_android.h

+// Copyright 2017 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 UI_EVENTS_DEVICES_INPUT_DEVICE_OBSERVER_ANDROID_H_
+#define UI_EVENTS_DEVICES_INPUT_DEVICE_OBSERVER_ANDROID_H_
+
+#include <jni.h>
+
+#include "base/observer_list.h"
+#include "ui/events/devices/input_device_event_observer.h"
+
+namespace base {
+template <typename T>
+struct DefaultSingletonTraits;
+}
+
+namespace ui {
+
+// This class is a singleton responsible to notify the
+// InputDeviceChangeObserver whenever an input change
+// happened on the Java side.
+class EVENTS_DEVICES_EXPORT InputDeviceObserverAndroid {
+ public:
+  static InputDeviceObserverAndroid* GetInstance();
+  ~InputDeviceObserverAndroid();
+
+  static bool RegisterInputDeviceObserver(JNIEnv* env);
+
+  void AddObserver(ui::InputDeviceEventObserver* observer);
+  void RemoveObserver(ui::InputDeviceEventObserver* observer);
+
+  void NotifyObserversTouchpadDeviceConfigurationChanged();
+  void NotifyObserversKeyboardDeviceConfigurationChanged();
+  void NotifyObserversMouseDeviceConfigurationChanged();
+
+ private:
+  InputDeviceObserverAndroid();
+
+  base::ObserverList<ui::InputDeviceEventObserver> observers_;
+
+  friend struct base::DefaultSingletonTraits<InputDeviceObserverAndroid>;
+  DISALLOW_COPY_AND_ASSIGN(InputDeviceObserverAndroid);
+};
+
+}  // namespace ui
+
+#endif  // UI_EVENTS_DEVICES_INPUT_DEVICE_OBSERVER_ANDROID_H_

ui/events/devices/input_device_observer_win.h

@@ -2,8 +2,8 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#ifndef CONTENT_BROWSER_RENDERER_HOST_INPUT_INPUT_DEVICE_OBSERVER_WIN_H_
-#define CONTENT_BROWSER_RENDERER_HOST_INPUT_INPUT_DEVICE_OBSERVER_WIN_H_
+#ifndef UI_EVENTS_DEVICES_INPUT_DEVICE_OBSERVER_WIN_H_
+#define UI_EVENTS_DEVICES_INPUT_DEVICE_OBSERVER_WIN_H_
 
 #include "base/observer_list.h"
 #include "base/win/registry.h"
@@ -45,4 +45,4 @@ class EVENTS_DEVICES_EXPORT InputDeviceObserverWin {
 
 }  // namespace ui
 
-#endif  // CONTENT_BROWSER_RENDERER_HOST_INPUT_INPUT_DEVICE_OBSERVER_WIN_H_
\ No newline at end of file
+#endif  // UI_EVENTS_DEVICES_INPUT_DEVICE_OBSERVER_WIN_H_
\ No newline at end of file