[cocos2d-x BUG1]CCLabelBMFont，字符作为child引用会存在错位

问题出现的条件：
设定宽度，且setLineBreakWithoutSpace(true)

问题描述：
处理自动分行逻辑时，会对字符做变换添加换行符\n，并再次调用createFontChars，此时字符序号存在错位可能。
注：自动添加的换行位前的字符tag正常，后续字符错。

解决方案：
tag编号需要过滤掉换行，这么处理后，不管是否存在字符变换，tag都是一致的。

修改后代码：（供参考 请比对源代码）

修改点：

void CCLabelBMFont::createFontChars()
{
    int nextFontPositionX = 0;
    int nextFontPositionY = 0;
    unsigned short prev = -1;
    int kerningAmount = 0;

    CCSize tmpSize = CCSizeZero;

    int longestLine = 0;
    unsigned int totalHeight = 0;

    unsigned int quantityOfLines = 1;
    unsigned int stringLen = m_sString ? cc_wcslen(m_sString) : 0;
    if (stringLen == 0)
    {
        return;
    }

    set<unsigned int> *charSet = m_pConfiguration->getCharacterSet();

    for (unsigned int i = 0; i < stringLen - 1; ++i)
    {
        unsigned short c = m_sString[i];
        if (c == '\n')
        {
            quantityOfLines++;
        }
    }

    totalHeight = m_pConfiguration->m_nCommonHeight * quantityOfLines;
    nextFontPositionY = 0-(m_pConfiguration->m_nCommonHeight - m_pConfiguration->m_nCommonHeight * quantityOfLines);
    
    CCRect rect;
    ccBMFontDef fontDef;

    for (unsigned int i = 0, j = 0; i < stringLen; i++, j++)
    {
        unsigned short c = m_sString[i];

        if (c == '\n')
        {
            nextFontPositionX = 0;
            nextFontPositionY -= m_pConfiguration->m_nCommonHeight;
            j--;
            continue;
        }
        
        if (charSet->find(c) == charSet->end())
        {
            CCLOGWARN("cocos2d::CCLabelBMFont: Attempted to use character not defined in this bitmap: %d", c);
            continue;
        }

        kerningAmount = this->kerningAmountForFirst(prev, c);
        
        tCCFontDefHashElement *element = NULL;

        // unichar is a short, and an int is needed on HASH_FIND_INT
        unsigned int key = c;
        HASH_FIND_INT(m_pConfiguration->m_pFontDefDictionary, &key, element);
        if (! element)
        {
            CCLOGWARN("cocos2d::CCLabelBMFont: characer not found %d", c);
            continue;
        }

        fontDef = element->fontDef;

        rect = fontDef.rect;
        rect = CC_RECT_PIXELS_TO_POINTS(rect);

        rect.origin.x += m_tImageOffset.x;
        rect.origin.y += m_tImageOffset.y;

        CCSprite *fontChar;

        bool hasSprite = true;
        fontChar = (CCSprite*)(this->getChildByTag(j));
        if (fontChar)
        {
            // Reusing previous Sprite
			fontChar->setVisible(true);
        }
        else
        {
            // New Sprite ? Set correct color, opacity, etc...
            if( 0 )
            {
				/* WIP: Doesn't support many features yet.
				 But this code is super fast. It doesn't create any sprite.
				 Ideal for big labels.
				 */
				fontChar = m_pReusedChar;
				fontChar->setBatchNode(NULL);
				hasSprite = false;
			}
            else
            {
                fontChar = new CCSprite();
                fontChar->initWithTexture(m_pobTextureAtlas->getTexture(), rect);
                addChild(fontChar, j, j);
                fontChar->release();
			}
            
            // Apply label properties
			fontChar->setOpacityModifyRGB(m_bIsOpacityModifyRGB);
            
			// Color MUST be set before opacity, since opacity might change color if OpacityModifyRGB is on
			fontChar->updateDisplayedColor(m_tDisplayedColor);
			fontChar->updateDisplayedOpacity(m_cDisplayedOpacity);
        }

        // updating previous sprite
        fontChar->setTextureRect(rect, false, rect.size);

        // See issue 1343. cast( signed short + unsigned integer ) == unsigned integer (sign is lost!)
        int yOffset = m_pConfiguration->m_nCommonHeight - fontDef.yOffset;
        CCPoint fontPos = ccp( (float)nextFontPositionX + fontDef.xOffset + fontDef.rect.size.width*0.5f + kerningAmount,
            (float)nextFontPositionY + yOffset - rect.size.height*0.5f * CC_CONTENT_SCALE_FACTOR() );
        fontChar->setPosition(CC_POINT_PIXELS_TO_POINTS(fontPos));

        // update kerning
        nextFontPositionX += fontDef.xAdvance + kerningAmount;
        prev = c;

        if (longestLine < nextFontPositionX)
        {
            longestLine = nextFontPositionX;
        }
        
        if (! hasSprite)
        {
            updateQuadFromSprite(fontChar, j);
        }
    }

    // If the last character processed has an xAdvance which is less that the width of the characters image, then we need
    // to adjust the width of the string to take this into account, or the character will overlap the end of the bounding
    // box
    if (fontDef.xAdvance < fontDef.rect.size.width)
    {
        tmpSize.width = longestLine + fontDef.rect.size.width - fontDef.xAdvance;
    }
    else
    {
        tmpSize.width = longestLine;
    }
    tmpSize.height = totalHeight;

    this->setContentSize(CC_SIZE_PIXELS_TO_POINTS(tmpSize));
}