servo: Merge #2965 - Move RenderState manipulation out of a loop so that we thrash it less (from zwarich:render-state-less)

Source-Repo: https://github.com/servo/servo
Source-Revision: 32b442b026e7f8fc61ed7390936143122cdd54f5

servo/src/components/gfx/render_task.rs

@@ -246,6 +246,8 @@ impl<C:RenderListener + Send> RenderTask<C> {
                         continue;
                     }
 
+                    self.compositor.set_render_state(RenderingRenderState);
+
                     let mut replies = Vec::new();
                     for ReRenderRequest { buffer_requests, scale, layer_id, epoch }
                           in requests.move_iter() {
@@ -256,6 +258,8 @@ impl<C:RenderListener + Send> RenderTask<C> {
                         }
                     }
 
+                    self.compositor.set_render_state(IdleRenderState);
+
                     debug!("render_task: returning surfaces");
                     self.compositor.paint(self.id, self.epoch, replies);
                 }
@@ -306,8 +310,6 @@ impl<C:RenderListener + Send> RenderTask<C> {
                 None => return,
             };
 
-            self.compositor.set_render_state(RenderingRenderState);
-
             // Divide up the layer into tiles.
             for tile in tiles.iter() {
                 // Optimize the display list for this tile.
@@ -444,7 +446,6 @@ impl<C:RenderListener + Send> RenderTask<C> {
             };
 
             replies.push((render_layer.id, layer_buffer_set));
-            self.compositor.set_render_state(IdleRenderState);
         })
     }
 }