Allow touch adjustment to return Shadow DOM node.

LayoutTests/touchadjustment/resources/touchadjustment.js

 /* function for finding the absolute bounds of a node (both inline and block) */
 function findAbsoluteBounds(node)
 {
     var bounds = node.getBoundingClientRect();
     return {
         left: bounds.left,
         top: bounds.top,
         width: bounds.right - bounds.left,
         height: bounds.bottom - bounds.top
     };
@@ skipping 45 matching lines @@
 function shouldBeWithin(adjustedPoint, targetArea) {
     if (adjustedPoint.x >= targetArea.left && adjustedPoint.y >= targetArea.top
         && adjustedPoint.x <= (targetArea.left + targetArea.width)
         && adjustedPoint.y <= (targetArea.top + targetArea.height)) {
         testPassed("adjusted point was within " + boundsToString(targetArea));
     } else {
         testFailed("adjusted node should be within " + boundsToString(targetArea)  + ". Was " + pointToString(adjustedPoint));
     }
 }
 
-function testTouchPoint(touchpoint, targetNode, allowTextNodes)
+function shadowHost(node)
+{
+    for (; node != null; node = node.parentNode) {
+        if (node.host)
+            return node.host;
+    }
+    return node;
+}
+
+function testTouchPoint(touchpoint, targetNode, allowTextNodes, disallowShadowDOM)
 {
     var adjustedNode = internals.touchNodeAdjustedToBestClickableNode(touchpoint.left, touchpoint.top, touchpoint.width, touchpoint.height, document);
     if (!allowTextNodes && adjustedNode && adjustedNode.nodeType == 3)
         adjustedNode = adjustedNode.parentNode;
+    if (disallowShadowDOM && adjustedNode && adjustedNode.nodeType == 1) {
+        while (shadowHost(adjustedNode))
+            adjustedNode = shadowHost(adjustedNode);
+    }
     shouldBeNode(adjustedNode, targetNode);
 }
 
 function testTouchPointContextMenu(touchpoint, targetNode, allowTextNodes)
 {
     var adjustedNode = internals.touchNodeAdjustedToBestContextMenuNode(touchpoint.left, touchpoint.top, touchpoint.width, touchpoint.height, document);
     if (!allowTextNodes && adjustedNode && adjustedNode.nodeType == 3)
         adjustedNode = adjustedNode.parentNode;
     shouldBeNode(adjustedNode, targetNode);
 }
@@ skipping 67 matching lines @@
         touchpoint.left += bounds.width / 2;
         touchpoint.top -= touchOffset;
         break;
     case 'bottom':
         touchpoint.left += bounds.width / 2;
         touchpoint.top += bounds.height + touchOffset;
     }
 
     return touchpoint;
 }