Introduce Find{Left,Right}BidiRun() and utilize in AdjustInlineBoxPositionForTextDirection()

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

 /*
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009 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 875 matching lines @@
     TextDirection primary_direction) {
   unsigned char level = inline_box->BidiLevel();
 
   if (inline_box->Direction() == primary_direction) {
     if (caret_offset == inline_box->CaretRightmostOffset()) {
       InlineBox* next_box = inline_box->NextLeafChild();
       if (!next_box || next_box->BidiLevel() >= level)
         return InlineBoxPosition(inline_box, caret_offset);
 
       level = next_box->BidiLevel();
-      InlineBox* prev_box = inline_box;
-      do {
-        prev_box = prev_box->PrevLeafChild();
-      } while (prev_box && prev_box->BidiLevel() > level);
+      InlineBox* const prev_box =
+          InlineBoxTraversal::FindLeftBidiRun(*inline_box, level);
 
       // For example, abc FED 123 ^ CBA
       if (prev_box && prev_box->BidiLevel() == level)
         return InlineBoxPosition(inline_box, caret_offset);
 
       // For example, abc 123 ^ CBA
       inline_box = InlineBoxTraversal::FindRightBoundaryOfEntireBidiRun(
           *inline_box, level);
       return InlineBoxPosition(inline_box, inline_box->CaretRightmostOffset());
     }
 
     if (IsStartOfDifferentDirection(inline_box))
       return InlineBoxPosition(inline_box, caret_offset);
 
     level = inline_box->PrevLeafChild()->BidiLevel();
-    InlineBox* next_box = inline_box;
-    do {
-      next_box = next_box->NextLeafChild();
-    } while (next_box && next_box->BidiLevel() > level);
+    InlineBox* const next_box =
+        InlineBoxTraversal::FindRightBidiRun(*inline_box, level);
 
     if (next_box && next_box->BidiLevel() == level)
       return InlineBoxPosition(inline_box, caret_offset);
 
     inline_box =
         InlineBoxTraversal::FindLeftBoundaryOfEntireBidiRun(*inline_box, level);
     return InlineBoxPosition(inline_box, inline_box->CaretLeftmostOffset());
   }
 
   if (caret_offset == inline_box->CaretLeftmostOffset()) {
@@ skipping 1152 matching lines @@
 
 IntRect ComputeTextRect(const EphemeralRangeInFlatTree& range) {
   return EnclosingIntRect(ComputeTextRectTemplate(range));
 }
 
 FloatRect ComputeTextFloatRect(const EphemeralRange& range) {
   return ComputeTextRectTemplate(range);
 }
 
 }  // namespace blink