Finish implementing ChromeVox Next active indicator.

chrome/common/extensions/api/automation.idl

Index: chrome/common/extensions/api/automation.idl
diff --git a/chrome/common/extensions/api/automation.idl b/chrome/common/extensions/api/automation.idl
index f9037c5878f85f3214f68d1043a126e0fc590f90..c6f02b9b9c3cce59b177f9cee2841106b663c388 100644
--- a/chrome/common/extensions/api/automation.idl
+++ b/chrome/common/extensions/api/automation.idl
@@ -334,9 +334,16 @@
     // The $(ref:automation.StateType)s describing this node.
     object state;
 
-    // The rendered location (as a bounding box) of this node within the frame.
+    // The rendered location (as a bounding box) of this node in global
+    // screen coordinates.
     automation.Rect location;
 
+    // Computes the bounding box of a subrange of this node in global screen
+    // coordinates. Returns the same as |location| if range information
+    // is not available. The start and end indices are zero-based offsets
+    // into the node's "name" string attribute.
+    static automation.Rect boundsForRange(long startIndex, long endIndex);
+
     // The purpose of the node, other than the role, if any.
     DOMString description;