Introduce ViewRoot forwarding 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 cc33b2dac09e8da12217a110430cce8147bc3c13..9cfcba60362472c94afa49d396a7b2649d291828 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
@@ -30,6 +30,7 @@ import org.chromium.content_public.browser.WebContents;
 import org.chromium.content_public.browser.WebContentsObserver;
 import org.chromium.ui.OverscrollRefreshHandler;
 import org.chromium.ui.accessibility.AXTextStyle;
+import org.chromium.ui.base.ViewRoot;
 
 import java.util.ArrayList;
 import java.util.List;
@@ -445,6 +446,11 @@ import java.util.UUID;
     }
 
     @Override
+    public void initViewRoot(ViewRoot viewRoot) {
+        nativeInitViewRoot(mNativeWebContentsAndroid, viewRoot);
+    }
+
+    @Override
     public int downloadImage(String url, boolean isFavicon, int maxBitmapSize,
             boolean bypassCache, ImageDownloadCallback callback) {
         return nativeDownloadImage(mNativeWebContentsAndroid,
@@ -545,6 +551,7 @@ import java.util.UUID;
             ContentBitmapCallback callback, Bitmap.Config config, float scale,
             float x, float y, float width, float height);
     private native void nativeReloadLoFiImages(long nativeWebContentsAndroid);
+    private native void nativeInitViewRoot(long nativeWebContentsAndroid, ViewRoot viewRoot);
     private native int nativeDownloadImage(long nativeWebContentsAndroid,
             String url, boolean isFavicon, int maxBitmapSize,
             boolean bypassCache, ImageDownloadCallback callback);