bootanimation: allow animation to specify background color

Some OEMs want to have a bootanimation (or parts of it) displayed on a
color other than black. They currently just use full-screen frames for
that, which wastes lots of memory and bandwidth. This change allows
each part of the animation to specify a background color that will be
applied outside of the frame images; if unspecified the background
will be black as it is now.

Bug: 16635599
Change-Id: Ibf008fc75c5aad891c86ba9e4ec0879b7a61b8bd
diff --git a/cmds/bootanimation/BootAnimation.h b/cmds/bootanimation/BootAnimation.h
index ba1c507..72cd62b 100644
--- a/cmds/bootanimation/BootAnimation.h
+++ b/cmds/bootanimation/BootAnimation.h
@@ -71,6 +71,7 @@
             String8 path;
             SortedVector<Frame> frames;
             bool playUntilComplete;
+            float backgroundColor[3];
         };
         int fps;
         int width;