Fix Javadoc-related lint erros under a.i.navigationbar

This is a mechanical cleanup CL.  There should be no behavior change.

Bug: 215443343
Test: prebuilts/checkstyle/checkstyle.py -f \
  frameworks/base/core/java/android/inputmethodservice/navigationbar/ \
  | grep "Missing a Javadoc comment"
Change-Id: I5cb365b69864a145e7eaf7ff4454c261324ab845

core/java/android/inputmethodservice/navigationbar/KeyButtonView.java

@@ -272,12 +272,13 @@ public class KeyButtonView extends ImageView implements ButtonInterface {
                 : KeyButtonRipple.Type.ROUNDED_RECT);
     }
 
+    @Override
     public void playSoundEffect(int soundConstant) {
         if (!mPlaySounds) return;
         mAudioManager.playSoundEffect(soundConstant);
     }
 
-    public void sendEvent(int action, int flags) {
+    private void sendEvent(int action, int flags) {
         sendEvent(action, flags, SystemClock.uptimeMillis());
     }
 

core/java/android/inputmethodservice/navigationbar/NavigationBarInflaterView.java

@@ -121,7 +121,7 @@ public final class NavigationBarInflaterView extends FrameLayout {
         return CONFIG_NAV_BAR_LAYOUT_HANDLE;
     }
 
-    public void setButtonDispatchers(SparseArray<ButtonDispatcher> buttonDispatchers) {
+    void setButtonDispatchers(SparseArray<ButtonDispatcher> buttonDispatchers) {
         mButtonDispatchers = buttonDispatchers;
         for (int i = 0; i < buttonDispatchers.size(); i++) {
             initiallyFill(buttonDispatchers.valueAt(i));
@@ -376,7 +376,7 @@ public final class NavigationBarInflaterView extends FrameLayout {
     }
     */
 
-    public static String extractSize(String buttonSpec) {
+    private static String extractSize(String buttonSpec) {
         if (!buttonSpec.contains(SIZE_MOD_START)) {
             return null;
         }
@@ -384,7 +384,7 @@ public final class NavigationBarInflaterView extends FrameLayout {
         return buttonSpec.substring(sizeStart + 1, buttonSpec.indexOf(SIZE_MOD_END));
     }
 
-    public static String extractButton(String buttonSpec) {
+    private static String extractButton(String buttonSpec) {
         if (!buttonSpec.contains(SIZE_MOD_START)) {
             return buttonSpec;
         }

core/java/android/inputmethodservice/navigationbar/NavigationBarView.java

@@ -181,7 +181,7 @@ public final class NavigationBarView extends FrameLayout {
         }
     }
 
-    public KeyButtonDrawable getBackDrawable() {
+    private KeyButtonDrawable getBackDrawable() {
         KeyButtonDrawable drawable = getDrawable(com.android.internal.R.drawable.ic_ime_nav_back);
         orientBackButton(drawable);
         return drawable;
@@ -233,6 +233,11 @@ public final class NavigationBarView extends FrameLayout {
         super.setLayoutDirection(layoutDirection);
     }
 
+    /**
+     * Updates the navigation icons based on {@code hints}.
+     *
+     * @param hints bit flags defined in {@link StatusBarManager}.
+     */
     public void setNavigationIconHints(int hints) {
         if (hints == mNavigationIconHints) return;
         final boolean newBackAlt = (hints & StatusBarManager.NAVIGATION_HINT_BACK_ALT) != 0;
@@ -250,15 +255,7 @@ public final class NavigationBarView extends FrameLayout {
         updateNavButtonIcons();
     }
 
-    public void setDisabledFlags(int disabledFlags) {
-        if (mDisabledFlags == disabledFlags) return;
-
-        mDisabledFlags = disabledFlags;
-
-        updateNavButtonIcons();
-    }
-
-    public void updateNavButtonIcons() {
+    private void updateNavButtonIcons() {
         // We have to replace or restore the back and home button icons when exiting or entering
         // carmode, respectively. Recents are not available in CarMode in nav bar so change
         // to recent icon is not required.
@@ -319,7 +316,7 @@ public final class NavigationBarView extends FrameLayout {
         mHorizontal.setVisibility(View.GONE);
     }
 
-    public void reorient() {
+    private void reorient() {
         updateCurrentView();
 
         final android.inputmethodservice.navigationbar.NavigationBarFrame frame =
@@ -372,6 +369,11 @@ public final class NavigationBarView extends FrameLayout {
         }
     }
 
+    /**
+     * Updates the dark intensity.
+     *
+     * @param intensity The intensity of darkness from {@code 0.0f} to {@code 1.0f}.
+     */
     public void setDarkIntensity(@FloatRange(from = 0.0f, to = 1.0f) float intensity) {
         for (int i = 0; i < mButtonDispatchers.size(); ++i) {
             mButtonDispatchers.valueAt(i).setDarkIntensity(intensity);

core/java/android/inputmethodservice/navigationbar/ReverseLinearLayout.java

@@ -30,9 +30,8 @@ import java.util.ArrayList;
 /**
  * Automatically reverses the order of children as they are added.
  * Also reverse the width and height values of layout params
- * @hide
  */
-public class ReverseLinearLayout extends LinearLayout {
+class ReverseLinearLayout extends LinearLayout {
 
     /** If true, the layout is reversed vs. a regular linear layout */
     private boolean mIsLayoutReverse;