Make clang plugin work with generated source files when ninja is used.
Make clang plugin work with generated source files when ninja is used.

ninja puts generated code into "ninja" instead of "out", so that directory needs
to be added to the list of ignored directories.

BUG=none
TEST=none


Review URL: http://codereview.chromium.org/7017039

git-svn-id: de016e52bd170d2d4f2344f9bf92d50478b649e0@85729 0039d316-1c4b-4281-b951-d872f2087c98

ropik/chromium,adobe/chromium,adobe/chromium,yitian134/chromium,gavinp/chromium,adobe/chromium,yitian134/chromium,yitian134/chromium,gavinp/chromium,ropik/chromium,gavinp/chromium,gavinp/chromium,adobe/chromium,ropik/chromium,ropik/chromium,adobe/chromium,yitian134/chromium,ropik/chromium,adobe/chromium,gavinp/chromium,ropik/chromium,yitian134/chromium,ropik/chromium,yitian134/chromium,yitian134/chromium,yitian134/chromium,yitian134/chromium,gavinp/chromium,gavinp/chromium,gavinp/chromium,adobe/chromium,ropik/chromium,adobe/chromium,ropik/chromium,adobe/chromium,gavinp/chromium,gavinp/chromium,adobe/chromium,adobe/chromium,yitian134/chromium