Delete dead-code for handling comments and invalid octal integers. These are already handled by the preprocessor.

TEST=WebGL conformance tests.

Review URL: https://codereview.appspot.com/8632053

git-svn-id: https://angleproject.googlecode.com/svn/branches/dx11proto@2228 736b8ea6-26fd-11df-bfd4-992fa37f6226