Move unusual character block logic to a helper function

ui/gfx/render_text_harfbuzz.h

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef UI_GFX_RENDER_TEXT_HARFBUZZ_H_
 #define UI_GFX_RENDER_TEXT_HARFBUZZ_H_
 
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/scoped_vector.h"
 #include "third_party/harfbuzz-ng/src/hb.h"
@@ skipping 74 matching lines @@
   virtual size_t TextIndexToLayoutIndex(size_t index) const OVERRIDE;
   virtual size_t LayoutIndexToTextIndex(size_t index) const OVERRIDE;
   virtual bool IsValidCursorIndex(size_t index) OVERRIDE;
   virtual void ResetLayout() OVERRIDE;
   virtual void EnsureLayout() OVERRIDE;
   virtual void DrawVisualText(Canvas* canvas) OVERRIDE;
 
  private:
   friend class RenderTextTest;
   FRIEND_TEST_ALL_PREFIXES(RenderTextTest, HarfBuzz_RunDirection);
+  FRIEND_TEST_ALL_PREFIXES(RenderTextTest, HarfBuzz_BreakRunsByUnicodeBlocks);
 
   // Return the run index that contains the argument; or the length of the
   // |runs_| vector if argument exceeds the text length or width.
   size_t GetRunContainingCaret(const SelectionModel& caret) const;
   size_t GetRunContainingXCoord(int x, int* offset) const;
 
   // Given a |run|, returns the SelectionModel that contains the logical first
   // or last caret position inside (not at a boundary of) the run.
   // The returned value represents a cursor/caret position without a selection.
   SelectionModel FirstSelectionModelInsideRun(
@@ skipping 15 matching lines @@
   std::vector<int32_t> logical_to_visual_;
 
   bool needs_layout_;
 
   DISALLOW_COPY_AND_ASSIGN(RenderTextHarfBuzz);
 };
 
 }  // namespace gfx
 
 #endif  // UI_GFX_RENDER_TEXT_HARFBUZZ_H_