Update Settings to use intensity settings as main preference keys

Updating the Settings app to allow setting the value off for key
HAPTIC_FEEDBACK_INTENSITY. This setting state is also copied onto
HAPTIC_FEEDBACK_ENABLED setting, so both should be in sync after this
change.

Similar logic is applied between RING_VIBRATION_INTENSITY and
VIBRATE_WHEN_RINGING.

This will not disable the hardware feedback since that one is controlled
by a separate setting key now.

The "vibrate for calls" was also removed and the single toggle for
"vibrate first then ring gradually" was moved into the "Vibration &
haptics" page.

Bug: 185351540
Test: [HapticFeedback|NotificationVibration|RingVibration][Intensity|Toggle]PreferenceControllerTest
      and manual testing of the AOSP settings app
Change-Id: I9c94cef331a1500a1272a601ba32667ca995ddab

src/com/android/settings/accessibility/VibrationPreferenceConfig.java

@@ -0,0 +1,126 @@
+/*
+ * Copyright (C) 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.settings.accessibility;
+
+import android.content.ContentResolver;
+import android.content.Context;
+import android.database.ContentObserver;
+import android.net.Uri;
+import android.os.Handler;
+import android.os.VibrationAttributes;
+import android.os.VibrationEffect;
+import android.os.Vibrator;
+import android.provider.Settings;
+
+import androidx.preference.Preference;
+
+import com.android.settingslib.core.AbstractPreferenceController;
+
+/**
+ * Vibration intensity settings configuration to be shared between different preference
+ * controllers that handle the same setting key.
+ */
+public abstract class VibrationPreferenceConfig {
+
+    protected final ContentResolver mContentResolver;
+    private final Vibrator mVibrator;
+    private final String mSettingKey;
+    private final int mDefaultIntensity;
+    private final VibrationAttributes mVibrationAttributes;
+
+    public VibrationPreferenceConfig(Context context, String settingKey, int vibrationUsage) {
+        mContentResolver = context.getContentResolver();
+        mVibrator = context.getSystemService(Vibrator.class);
+        mSettingKey = settingKey;
+        mDefaultIntensity = mVibrator.getDefaultVibrationIntensity(vibrationUsage);
+        mVibrationAttributes = new VibrationAttributes.Builder()
+                .setUsage(vibrationUsage)
+                .build();
+    }
+
+    /** Return the setting key for this setting preference. */
+    public String getSettingKey() {
+        return mSettingKey;
+    }
+
+    /** Returns the default intensity to be displayed when the setting value is not set. */
+    public int getDefaultIntensity() {
+        return mDefaultIntensity;
+    }
+
+    /** Reads setting value for corresponding {@link VibrationPreferenceConfig} */
+    public int readIntensity() {
+        return Settings.System.getInt(mContentResolver, mSettingKey, mDefaultIntensity);
+    }
+
+    /** Update setting value for corresponding {@link VibrationPreferenceConfig} */
+    public boolean updateIntensity(int intensity) {
+        return Settings.System.putInt(mContentResolver, mSettingKey, intensity);
+    }
+
+    /** Play a vibration effect with intensity just selected by the user. */
+    public void playVibrationPreview() {
+        mVibrator.vibrate(VibrationEffect.createPredefined(VibrationEffect.EFFECT_CLICK),
+                mVibrationAttributes);
+    }
+
+    /** {@link ContentObserver} for a setting described by a {@link VibrationPreferenceConfig}. */
+    public static final class SettingObserver extends ContentObserver {
+        private final Uri mUri;
+        private AbstractPreferenceController mPreferenceController;
+        private Preference mPreference;
+
+        /** Creates observer for given preference. */
+        public SettingObserver(VibrationPreferenceConfig preferenceConfig) {
+            super(new Handler(/* async= */ true));
+            mUri = Settings.System.getUriFor(preferenceConfig.getSettingKey());
+        }
+
+        @Override
+        public void onChange(boolean selfChange, Uri uri) {
+            if (mUri.equals(uri) && mPreferenceController != null && mPreference != null) {
+                mPreferenceController.updateState(mPreference);
+            }
+        }
+
+        /**
+         * Register this observer to given {@link ContentResolver}, to be called from lifecycle
+         * {@code onStart} method.
+         */
+        public void register(ContentResolver contentResolver) {
+            contentResolver.registerContentObserver(mUri, /* notifyForDescendants= */ false, this);
+        }
+
+        /**
+         * Unregister this observer from given {@link ContentResolver}, to be called from lifecycle
+         * {@code onStop} method.
+         */
+        public void unregister(ContentResolver contentResolver) {
+            contentResolver.unregisterContentObserver(this);
+        }
+
+        /**
+         * Binds this observer to given controller and preference, once it has been displayed to the
+         * user.
+         */
+        public void onDisplayPreference(AbstractPreferenceController controller,
+                Preference preference) {
+            mPreferenceController = controller;
+            mPreference = preference;
+        }
+    }
+}