Rockbox

Add support for two new scroll styles, STYLE_NODRAW and STYLE_CUSTOM, with STYLE_CUSTOM causing the draw to be done via a hook (set with lcd_set_style_hook). lcd_puts_stroll_style_offset also returns a struct scrollinfo pointer. This may be used in conjunction with STYLE_NODRAW to redraw the scrolling text in a plugin which draws other graphics to the same part of the screen, by drawing the text using the offset in the struct scrollinfo after the background graphics have been drawn. My latest patch from  FS#4817  is required, as it consolidates styled text drawing in one function, making it easier to replace the normal draw with a call to the hook, and reducing the binsize impact of this feature as well.

Support for core text scrolling in PictureFlow plugin to follow .

 b/apps/plugin.c                        |    3 
 b/apps/plugin.h                        |    9 ++
 b/apps/screen_access.h                 |    5 -
 b/firmware/drivers/lcd-bitmap-common.c |  114 +++++++++++++++++++++------------
 b/firmware/export/lcd.h                |   13 ++-
 5 files changed, 97 insertions(+), 47 deletions(-)