Enable BrowserEncoding tests for EUC-KR

They're disabled while waiting for a Blink roll containing r=159125

The initial CL is https://codereview.chromium.org/25769005/

BUG=277027,95963
TEST=browser test: BrowserEncodingTest.* and EncodingAlias*.
TBR=thakis

Review URL: https://codereview.chromium.org/26504004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@227863 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 227863