Hide the autofill keyboard accessory when the keyboard hides.

ui/android/java/src/org/chromium/ui/base/WindowAndroid.java

Index: ui/android/java/src/org/chromium/ui/base/WindowAndroid.java
diff --git a/ui/android/java/src/org/chromium/ui/base/WindowAndroid.java b/ui/android/java/src/org/chromium/ui/base/WindowAndroid.java
index 86cb72dffbcdbea0a1779f4525d9fc4d3fa3e500..050e09bd2448531fe81611a2852ff026b4890094 100644
--- a/ui/android/java/src/org/chromium/ui/base/WindowAndroid.java
+++ b/ui/android/java/src/org/chromium/ui/base/WindowAndroid.java
@@ -26,6 +26,7 @@ import org.chromium.ui.VSyncMonitor;
 import java.lang.ref.WeakReference;
 import java.util.HashMap;
 import java.util.HashSet;
+import java.util.LinkedList;
 
 /**
  * The window base class that has the minimum functionality.
@@ -58,6 +59,15 @@ public class WindowAndroid {
 
     private ViewGroup mKeyboardAccessoryView;
 
+    /**
+     * An interface to notify listeners of changes in the soft keyboard's visibility.
+     */
+    public interface KeyboardVisibilityListener {
+        public void keyboardVisibilityChanged(boolean isShowing);
+    }
+    private LinkedList<KeyboardVisibilityListener> mKeyboardVisibilityListeners =
+            new LinkedList<KeyboardVisibilityListener>();
+
     private final VSyncMonitor.Listener mVSyncListener = new VSyncMonitor.Listener() {
         @Override
         public void onVSync(VSyncMonitor monitor, long vsyncTimeMicros) {
@@ -327,6 +337,34 @@ public class WindowAndroid {
     }
 
     /**
+     * Adds a listener that is updated of keyboard visibility changes. This works as a best guess.
+     * {@see UiUtils.isKeyboardShowing}
+     */
+    public void addKeyboardVisibilityListener(KeyboardVisibilityListener listener) {
+        mKeyboardVisibilityListeners.add(listener);
+    }
+
+    /**
+     * {@see addKeyboardVisibilityListener()}.
+     */
+    public void removeKeyboardVisibilityListener(KeyboardVisibilityListener listener) {
+        mKeyboardVisibilityListeners.remove(listener);
+    }
+
+    /**
+     * To be called when the keyboard visibility state has changed. Informs listeners of the state
+     * change.
+     */
+    public void keyboardVisibilityChanged(boolean isShowing) {
+        // Clone the list in case a listener tries to remove itself during the callback.
+        LinkedList<KeyboardVisibilityListener> listeners =
+                new LinkedList<KeyboardVisibilityListener>(mKeyboardVisibilityListeners);
+        for (KeyboardVisibilityListener listener : listeners) {
+            listener.keyboardVisibilityChanged(isShowing);
+        }
+    }
+
+    /**
      * Start a post-layout animation on top of web content.
      *
      * By default, Android optimizes what it shows on top of SurfaceViews (saves power).