code cleanup: rename G.afbreek --> is_break, G.rendering --> is_rendering

source/blender/editors/space_sequencer/sequencer_draw.c

@@ -849,7 +849,7 @@ void draw_image_seq(const bContext *C, Scene *scene, ARegion *ar, SpaceSeq *sseq
 	UI_view2d_curRect_validate(v2d);
 
 	/* only initialize the preview if a render is in progress */
-	if (G.rendering)
+	if (G.is_rendering)
 		return;
 
 	context = BKE_sequencer_new_render_data(bmain, scene, rectx, recty, proxy_size);

source/blender/editors/space_sequencer/sequencer_edit.c

@@ -212,7 +212,7 @@ static void seq_proxy_build_job(const bContext *C)
 	SEQ_END
 
 	if (!WM_jobs_is_running(steve)) {
-		G.afbreek = 0;
+		G.is_break = FALSE;
 		WM_jobs_start(CTX_wm_manager(C), steve);
 	}