Bugfixes from own collection:

- when renderwin exists, but not used for render, the ESC timer check still
  could return ESC event, due to missing flag clearing.
  (For example in sequencer, a scene strip did not update on frame advance)

- option 'single layer' set in combination with render "Do Sequence" didn't
  free the pushed layers.

source/blender/render/intern/source/pipeline.c

@@ -181,6 +181,9 @@ static void free_render_result(RenderResult *res)
 /* all layers except the active one get temporally pushed away */
 static void push_render_result(Render *re)
 {
+	/* officially pushed result should be NULL... error can happen with do_seq */
+	free_render_result(re->pushedresult);
+	
 	re->pushedresult= re->result;
 	re->result= NULL;
 }

source/blender/src/renderwin.c

@@ -733,7 +733,6 @@ static void renderwin_init_display_cb(RenderResult *rr)
 			}
 
 			renderwin_reset_view(render_win);
-			render_win->flags&= ~RW_FLAGS_ESCAPE;
 			render_win->active= 1;
 		}
 		/* make sure we are in normal draw again */
@@ -1165,6 +1164,9 @@ void BIF_init_render_callbacks(Render *re, int do_display)
 	RE_error_cb(re, error_cb);
 	
 	G.afbreek= 0;
+	if(render_win)
+		render_win->flags &= ~RW_FLAGS_ESCAPE;
+
 	/* start esc timer. ensure it happens once only */
 	if(esc_timer_set==0)
 		init_test_break_callback();

source/blender/src/sequence.c

@@ -903,7 +903,7 @@ static void do_build_seq_ibuf(Sequence * seq, int cfra)
 				if(G.rendering)
 					re= RE_NewRender(" do_build_seq_ibuf");	
 				else
-					re= RE_NewRender(seq->scene->id.name);
+					re= RE_NewRender(sce->id.name);
 				
 				/* prevent eternal loop */
 				doseq= sce->r.scemode & R_DOSEQ;