Introduce ComputeInlineBoxPositionForAtomicInline

This patch wraps code in ComputeInlineBoxPosition into a new
function, so that the code flow becomes clearer.

Bug: 771398
Change-Id: I6b702f736fe7e21b454aa207180aebadeba63699
Reviewed-on: https://chromium-review.googlesource.com/777702Reviewed-by: Yoichi Osato <yoichio@chromium.org>
Reviewed-by: Yoshifumi Inoue <yosin@chromium.org>
Commit-Queue: Xiaocheng Hu <xiaochengh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#517895}

third_party/WebKit/Source/core/editing/InlineBoxPosition.cpp

@@ -264,6 +264,23 @@ InlineBoxPosition ComputeInlineBoxPositionForTextNode(
       primary_direction);
 }
 
+InlineBoxPosition ComputeInlineBoxPositionForAtomicInline(
+    const LayoutObject* layout_object,
+    int caret_offset,
+    TextDirection primary_direction) {
+  if (!layout_object->IsBox())
+    return InlineBoxPosition();
+  InlineBox* const inline_box = ToLayoutBox(layout_object)->InlineBoxWrapper();
+  if (!inline_box)
+    return InlineBoxPosition();
+  if ((caret_offset > inline_box->CaretMinOffset() &&
+       caret_offset < inline_box->CaretMaxOffset()))
+    return InlineBoxPosition(inline_box, caret_offset);
+  return AdjustInlineBoxPositionForTextDirection(
+      inline_box, caret_offset, layout_object->Style()->GetUnicodeBidi(),
+      primary_direction);
+}
+
 template <typename Strategy>
 InlineBoxPosition ComputeInlineBoxPositionTemplate(
     const PositionTemplate<Strategy>& position,
@@ -284,18 +301,7 @@ InlineBoxPosition ComputeInlineBoxPositionTemplate(
   }
 
   if (layout_object->IsAtomicInlineLevel()) {
-    // TODO(xiaochengh): Wrap the following into a function.
-    if (!layout_object->IsBox())
-      return InlineBoxPosition();
-    InlineBox* const inline_box =
-        ToLayoutBox(layout_object)->InlineBoxWrapper();
-    if (!inline_box)
-      return InlineBoxPosition();
-    if ((caret_offset > inline_box->CaretMinOffset() &&
-         caret_offset < inline_box->CaretMaxOffset()))
-      return InlineBoxPosition(inline_box, caret_offset);
-    return AdjustInlineBoxPositionForTextDirection(
-        inline_box, caret_offset, layout_object->Style()->GetUnicodeBidi(),
+    return ComputeInlineBoxPositionForAtomicInline(layout_object, caret_offset,
                                                    primary_direction);
   }