Reland r36541 (which went in without any commit log by some magic). Was rever...

Reland r36541 (which went in without any commit log by some magic). Was reverted in r36550. Now I'm relanding with the full description. 

Port back CLD to Linux and Mac by replacing Windows API calls with ICU's equivalent APIs for normalization. 

I also fixed bug 23553 (Traditional Chinese is not detected) by calling LanguageCode instead of LanguageCode_ISO_639_1. The latter covers only ISO 639-1, but there are languages detected by CLD not covered by ISO 639-1. In that case, ISO 639-2 is used. In case even ISO 639-2 does not cover (e.g. Traditional Chinese), another fallback is taken by LanguageCode. 

The html file for CLD testing (french_sentence.html) is explicitly labelled with charset=ISO-8859-1.

Original Review: http://codereview.chromium.org/523108

BUG=25206, 23553
TEST=1. CLD is built on Linux/Mac
     2. The following test pass:
       - unit_tests: Extension*.DetectTabLang* and CompactLangDet*.* 
       - browser_tests: ExtensionBrowserTest.Toolstrip 
     3. Install the 'cld extension' in chrome/common/extensions/docs/examples/api/i18n/cld and go to http://news.google.com.tw and 'zh-TW' shows up in the language badge at the upper right (upper-left in he/ar Chrome) corner. 
TBR=jcampan







Review URL: http://codereview.chromium.org/545123

TBR=jshin@chromium.org
Review URL: http://codereview.chromium.org/551070

TBR=jshin@chromium.org

Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=36552