Using yy_scan_string, which flushes the old buffer does not work. GLSL requires that each input string is concatenated, but yy_scan_string treats each string individually. Added a custom YY_INPUT which maintains the continuity between each string.
Review URL: https://codereview.appspot.com/6130045

git-svn-id: https://angleproject.googlecode.com/svn/trunk@1066 736b8ea6-26fd-11df-bfd4-992fa37f6226