Don't crash on a null pointer passed to glBufferData TRAC #11528 * Initialise buffer to 0 if BufferData is called with data = NULL (special case: if not resizing, just leave the old data in place). * BufferSubData ignores calls with data = NULL * Replace Buffer::data_t with GLubyte. Author: Andrew Lewycky Signed-off-by: Shannon Woods Signed-off-by: Daniel Koch git-svn-id: https://angleproject.googlecode.com/svn/trunk@59 736b8ea6-26fd-11df-bfd4-992fa37f6226