Break HarfBuzzShaper::collectHarfBuzzRuns apart

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 541 matching lines @@
         return false;
 
     return true;
 }
 
 FloatPoint HarfBuzzShaper::adjustStartPoint(const FloatPoint& point)
 {
     return point + m_startOffset;
 }
 
+static inline int handleMultipleUChar(
+    UChar32 character,
+    unsigned clusterLength,
+    const SimpleFontData* currentFontData,
+    const UChar* currentCharacterPosition,
+    const UChar* markCharactersEnd,
+    const UChar* normalizedBufferEnd)
+{
+    if (U_GET_GC_MASK(character) & U_GC_M_MASK) {
+        int markLength = clusterLength;
+        while (markCharactersEnd < normalizedBufferEnd) {
+            UChar32 nextCharacter;
+            int nextCharacterLength = 0;
+            U16_NEXT(markCharactersEnd, nextCharacterLength, normalizedBufferEnd - markCharactersEnd, nextCharacter);
+            if (!(U_GET_GC_MASK(nextCharacter) & U_GC_M_MASK))
+                break;
+            markLength += nextCharacterLength;
+            markCharactersEnd += nextCharacterLength;
+        }
+
+        if (currentFontData->canRenderCombiningCharacterSequence(currentCharacterPosition, markCharactersEnd - currentCharacterPosition)) {
+            return markLength;
+        }
+    }
+    return 0;
+}
+
 bool HarfBuzzShaper::collectHarfBuzzRuns()
 {
     const UChar* normalizedBufferEnd = m_normalizedBuffer.get() + m_normalizedBufferLength;
     SurrogatePairAwareTextIterator iterator(m_normalizedBuffer.get(), 0, m_normalizedBufferLength, m_normalizedBufferLength);
     UChar32 character;
     unsigned clusterLength = 0;
     unsigned startIndexOfCurrentRun = 0;
     if (!iterator.consume(character, clusterLength))
         return false;
 
     const SimpleFontData* nextFontData = m_font->glyphDataForCharacter(character, false).fontData;
     UErrorCode errorCode = U_ZERO_ERROR;
     UScriptCode nextScript = uscript_getScript(character, &errorCode);
     if (U_FAILURE(errorCode))
         return false;
 
     do {
         const UChar* currentCharacterPosition = iterator.characters();
         const SimpleFontData* currentFontData = nextFontData;
         UScriptCode currentScript = nextScript;
 
         for (iterator.advance(clusterLength); iterator.consume(character, clusterLength); iterator.advance(clusterLength)) {
             if (Font::treatAsZeroWidthSpace(character))
                 continue;
 
-            if (U_GET_GC_MASK(character) & U_GC_M_MASK) {
-                int markLength = clusterLength;
-                const UChar* markCharactersEnd = iterator.characters() + clusterLength;
-                while (markCharactersEnd < normalizedBufferEnd) {
-                    UChar32 nextCharacter;
-                    int nextCharacterLength = 0;
-                    U16_NEXT(markCharactersEnd, nextCharacterLength, normalizedBufferEnd - markCharactersEnd, nextCharacter);
-                    if (!(U_GET_GC_MASK(nextCharacter) & U_GC_M_MASK))
-                        break;
-                    markLength += nextCharacterLength;
-                    markCharactersEnd += nextCharacterLength;
-                }
-
-                if (currentFontData->canRenderCombiningCharacterSequence(currentCharacterPosition, markCharactersEnd - currentCharacterPosition)) {
-                    clusterLength = markLength;
-                    continue;
-                }
+            int length = handleMultipleUChar(character, clusterLength, currentFontData, currentCharacterPosition, iterator.characters() + clusterLength, normalizedBufferEnd);
+            if (length) {
+                clusterLength = length;
+                continue;
             }
 
             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;
@@ skipping 266 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