Break HarfBuzz run creation into separate function

Source/platform/fonts/harfbuzz/HarfBuzzShaper.cpp

 /*
  * Copyright (c) 2012 Google Inc. All rights reserved.
  * Copyright (C) 2013 BlackBerry Limited. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
@@ skipping 609 matching lines @@
             nextFontData = m_font->glyphDataForCharacter(character, false).fontData;
             nextScript = uscript_getScript(character, &errorCode);
             if (U_FAILURE(errorCode))
                 return false;
             if ((nextFontData != currentFontData) || ((currentScript != nextScript) && (nextScript != USCRIPT_INHERITED) && (!uscript_hasScript(character, currentScript))))
                 break;
             if (nextScript == USCRIPT_INHERITED)
                 nextScript = currentScript;
             currentCharacterPosition = iterator.characters();
         }
-        unsigned numCharactersOfCurrentRun = iterator.currentCharacter() - startIndexOfCurrentRun;
-        hb_script_t script = hb_icu_script_to_script(currentScript);
-        m_harfBuzzRuns.append(HarfBuzzRun::create(currentFontData, startIndexOfCurrentRun, numCharactersOfCurrentRun, m_run.direction(), script));
+        addHarfBuzzRun(startIndexOfCurrentRun, iterator.currentCharacter(), currentFontData, currentScript);
         currentFontData = nextFontData;
         startIndexOfCurrentRun = iterator.currentCharacter();
     } while (iterator.consume(character, clusterLength));
 
     return !m_harfBuzzRuns.isEmpty();
 }
 
+void HarfBuzzShaper::addHarfBuzzRun(unsigned startCharacter,
+    unsigned endCharacter, const SimpleFontData* fontData,
+    UScriptCode script)
+{
+    ASSERT(endCharacter > startCharacter);
+    ASSERT(script != USCRIPT_INVALID_CODE);
+    return m_harfBuzzRuns.append(HarfBuzzRun::create(fontData,
+        startCharacter, endCharacter - startCharacter,
+        m_run.direction(), hb_icu_script_to_script(script)));
+}
+
 static const uint16_t* toUint16(const UChar* src)
 {
     // FIXME: This relies on undefined behavior however it works on the
     // current versions of all compilers we care about and avoids making
     // a copy of the string.
     COMPILE_ASSERT(sizeof(UChar) == sizeof(uint16_t), UChar_is_the_same_size_as_uint16_t);
     return reinterpret_cast<const uint16_t*>(src);
 }
 
 bool HarfBuzzShaper::shapeHarfBuzzRuns()
@@ skipping 244 matching lines @@
     if (!foundToX)
         toX = m_run.rtl() ? 0 : m_totalWidth;
 
     // Using floorf() and roundf() as the same as mac port.
     if (fromX < toX)
         return FloatRect(floorf(point.x() + fromX), point.y(), roundf(toX - fromX), height);
     return FloatRect(floorf(point.x() + toX), point.y(), roundf(fromX - toX), height);
 }
 
 } // namespace WebCore