Introduce ViewRoot to forward input/view events to native

content/public/android/java/src/org/chromium/content/browser/webcontents/WebContentsImpl.java

Index: content/public/android/java/src/org/chromium/content/browser/webcontents/WebContentsImpl.java
diff --git a/content/public/android/java/src/org/chromium/content/browser/webcontents/WebContentsImpl.java b/content/public/android/java/src/org/chromium/content/browser/webcontents/WebContentsImpl.java
index 2803d37f91dad0afd556110c621b488b1f9babc3..2e733d3e32ad6f1ac83832f9bfa0b94300e60bc5 100644
--- a/content/public/android/java/src/org/chromium/content/browser/webcontents/WebContentsImpl.java
+++ b/content/public/android/java/src/org/chromium/content/browser/webcontents/WebContentsImpl.java
@@ -29,6 +29,7 @@ import org.chromium.content_public.browser.NavigationController;
 import org.chromium.content_public.browser.WebContents;
 import org.chromium.content_public.browser.WebContentsObserver;
 import org.chromium.ui.accessibility.AXTextStyle;
+import org.chromium.ui.base.EventHandler;
 
 import java.util.ArrayList;
 import java.util.List;
@@ -98,6 +99,8 @@ import java.util.UUID;
     // the same life time as native MediaSession.
     private MediaSessionImpl mMediaSession;
 
+    private EventHandler mEventHandler;
+
     private WebContentsImpl(
             long nativeWebContentsAndroid, NavigationController navigationController) {
         mNativeWebContentsAndroid = nativeWebContentsAndroid;
@@ -481,6 +484,14 @@ import java.util.UUID;
         sizes.add(new Rect(0, 0, width, height));
     }
 
+    @Override
+    public EventHandler getEventHandler() {
+        if (mEventHandler == null) {
+            mEventHandler = new EventHandler(nativeGetNativeView(mNativeWebContentsAndroid));
+        }
+        return mEventHandler;
+    }
+
     // This is static to avoid exposing a public destroy method on the native side of this class.
     private static native void nativeDestroyWebContents(long webContentsAndroidPtr);
 
@@ -541,4 +552,5 @@ import java.util.UUID;
             String url, boolean isFavicon, int maxBitmapSize,
             boolean bypassCache, ImageDownloadCallback callback);
     private native void nativeDismissTextHandles(long nativeWebContentsAndroid);
+    private native long nativeGetNativeView(long nativeWebContentsAndroid);
 }