Introduce firstRangeOf() as replacement of VisibleSelection::firstRange()

Source/modules/accessibility/AXLayoutObject.cpp

 /*
 * Copyright (C) 2008 Apple Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1.  Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 * 2.  Redistributions in binary form must reproduce the above copyright
@@ skipping 1832 matching lines @@
 AXObject::AXRange AXLayoutObject::selection() const
 {
     AXRange textSelection = textControlSelection();
     if (textSelection.isValid())
         return textSelection;
 
     if (!layoutObject() || !layoutObject()->frame())
         return AXRange();
 
     VisibleSelection selection = layoutObject()->frame()->selection().selection();
-    RefPtrWillBeRawPtr<Range> selectionRange = selection.firstRange();
+    RefPtrWillBeRawPtr<Range> selectionRange = firstRangeOf(selection);
     if (!selectionRange)
         return AXRange();
 
     int anchorOffset = selectionRange->startOffset();
     ASSERT(anchorOffset >= 0);
     int focusOffset = selectionRange->endOffset();
     ASSERT(focusOffset >= 0);
 
     Node* anchorNode = selectionRange->startContainer();
     ASSERT(anchorNode);
@@ skipping 40 matching lines @@
 AXObject::AXRange AXLayoutObject::selectionUnderObject() const
 {
     AXRange textSelection = textControlSelection();
     if (textSelection.isValid())
         return textSelection;
 
     if (!layoutObject() || !layoutObject()->frame())
         return AXRange();
 
     VisibleSelection selection = layoutObject()->frame()->selection().selection();
-    RefPtrWillBeRawPtr<Range> selectionRange = selection.firstRange();
+    RefPtrWillBeRawPtr<Range> selectionRange = firstRangeOf(selection);
     ContainerNode* parentNode = node()->parentNode();
     int nodeIndex = node()->nodeIndex();
     if (!selectionRange
         // Selection is contained in node.
         || !(parentNode
         && selectionRange->comparePoint(parentNode, nodeIndex, IGNORE_EXCEPTION) < 0
         && selectionRange->comparePoint(parentNode, nodeIndex + 1, IGNORE_EXCEPTION) > 0)) {
         return AXRange();
     }
 
@@ skipping 722 matching lines @@
         if (label && label->layoutObject()) {
             LayoutRect labelRect = axObjectCache().getOrCreate(label)->elementRect();
             result.unite(labelRect);
         }
     }
 
     return result;
 }
 
 } // namespace blink