[Android] Allow text handles to observe position of "parent" view

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 88785c177e4d7083df2badb0f07f756141072d1b..284d06b4fcd9e22b80e934ad127ca162cd458d64 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
@@ -55,6 +55,7 @@ import com.google.common.annotations.VisibleForTesting;
 
 import org.chromium.base.CalledByNative;
 import org.chromium.base.JNINamespace;
+import org.chromium.base.PositionObserver;
 import org.chromium.base.WeakContext;
 import org.chromium.content.R;
 import org.chromium.content.browser.ContentViewGestureHandler.MotionEventDelegate;
@@ -377,6 +378,8 @@ import java.util.Map;
 
     private Runnable mDeferredHandleFadeInRunnable;
 
+    private PositionObserver mPositionObserver;
+
     // Size of the viewport in physical pixels as set from onSizeChanged.
     private int mViewportWidthPix;
     private int mViewportHeightPix;
@@ -717,6 +720,7 @@ import java.util.Map;
         mHardwareAccelerated = hasHardwareAcceleration(mContext);
 
         mContainerView = containerView;
+        mPositionObserver = new PositionObserver(mContainerView);
 
         int windowNativePointer = windowAndroid != null ? windowAndroid.getNativePointer() : 0;
 
@@ -2017,7 +2021,8 @@ import java.util.Map;
 
     private SelectionHandleController getSelectionHandleController() {
         if (mSelectionHandleController == null) {
-            mSelectionHandleController = new SelectionHandleController(getContainerView()) {
+            mSelectionHandleController = new SelectionHandleController(
+                    getContainerView(), mPositionObserver) {
                 @Override
                 public void selectBetweenCoordinates(int x1, int y1, int x2, int y2) {
                     if (mNativeContentViewCore != 0 && !(x1 == x2 && y1 == y2)) {
@@ -2043,7 +2048,8 @@ import java.util.Map;
 
     private InsertionHandleController getInsertionHandleController() {
         if (mInsertionHandleController == null) {
-            mInsertionHandleController = new InsertionHandleController(getContainerView()) {
+            mInsertionHandleController = new InsertionHandleController(
+                    getContainerView(), mPositionObserver) {
                 private static final int AVERAGE_LINE_HEIGHT = 14;
 
                 @Override