Plumb smooth scrolling in Chromium compositor

content/public/android/java/src/org/chromium/content/browser/ContentViewCore.java

Index: content/public/android/java/src/org/chromium/content/browser/ContentViewCore.java
diff --git a/content/public/android/java/src/org/chromium/content/browser/ContentViewCore.java b/content/public/android/java/src/org/chromium/content/browser/ContentViewCore.java
index ead6ba459e355e9c4d9937c9a7076f2ecd0b1be1..7682956364a78aa368d5586dd50550cd24977be2 100644
--- a/content/public/android/java/src/org/chromium/content/browser/ContentViewCore.java
+++ b/content/public/android/java/src/org/chromium/content/browser/ContentViewCore.java
@@ -1245,8 +1245,7 @@ public class ContentViewCore implements
     }
 
     public boolean isScrollInProgress() {
-        return mTouchScrollInProgress || mPotentiallyActiveFlingCount > 0
-                || getContentViewClient().isExternalScrollActive();
+        return mTouchScrollInProgress || mPotentiallyActiveFlingCount > 0;
     }
 
     @SuppressWarnings("unused")
@@ -1355,6 +1354,10 @@ public class ContentViewCore implements
         nativeFlingStart(mNativeContentViewCore, timeMs, 0, 0, velocityX, velocityY, true);
     }
 
+    public void smoothScroll(int targetX, int targetY, long durationMs) {

[jdduke (slow), 2015/07/28 15:54:31]

Nit: Javadoc.

[hush (inactive), 2015/07/28 21:36:46]

Done.

+        mWebContents.smoothScroll(targetX, targetY, durationMs);
+    }
+
     /**
      * Cancel any fling gestures active.
      * @param timeMs Current time (in milliseconds).
@@ -1396,9 +1399,6 @@ public class ContentViewCore implements
                             computeVerticalScrollOffset(),
                             computeVerticalScrollExtent());
                     break;
-                case GestureEventType.FLING_CANCEL:
-                    listener.onFlingCancelGesture();
-                    break;
                 case GestureEventType.SCROLL_START:
                     listener.onScrollStarted(
                             computeVerticalScrollOffset(),