res: Embed FPS into icon_installing.png.

We allow vendor-specific icon installing image but have defined private
animation_fps that can't be overridden. This CL changes the image
generator to optionally embed FPS (otherwise use the default value of
20) into the generated image.

For wear devices, they are using individual images instead of the
interlaced one. Change the animation_fps from private to protected so
that it can be customized.

Bug: 26009230
Change-Id: I9fbf64ec717029d4c54f72316f6cb079e8dbfb5e
diff --git a/wear_ui.h b/wear_ui.h
index 839a264..63c1b6e 100644
--- a/wear_ui.h
+++ b/wear_ui.h
@@ -79,6 +79,9 @@
     int intro_frames;
     int loop_frames;
+    // Number of frames per sec (default: 30) for both of intro and loop.
+    int animation_fps;
     Icon currentIcon;
@@ -86,8 +89,6 @@
     int current_frame;
-    int animation_fps;
     bool rtl_locale;
     pthread_mutex_t updateMutex;