Refactor RenderWidgetHost::set_paint_observer()

chrome/browser/tab_contents/thumbnail_generator.cc

Index: chrome/browser/tab_contents/thumbnail_generator.cc
diff --git a/chrome/browser/tab_contents/thumbnail_generator.cc b/chrome/browser/tab_contents/thumbnail_generator.cc
index 1844f67a700c9bd7599a3d9cd7334ba75b71ddfa..a26bca08c39766143ca231983fa211eaaa5bd4ae 100644
--- a/chrome/browser/tab_contents/thumbnail_generator.cc
+++ b/chrome/browser/tab_contents/thumbnail_generator.cc
@@ -172,6 +172,45 @@ void ThumbnailGenerator::StartThumbnailing() {
   }
 }
 
+void ThumbnailGenerator::MonitorRenderer(RenderWidgetHost* renderer,
+                                         bool monitor) {
+  Source<RenderWidgetHost> renderer_source = Source<RenderWidgetHost>(renderer);
+  bool currently_monitored =
+      registrar_.IsRegistered(
+        this,
+        NotificationType::RENDER_WIDGET_HOST_WILL_DESTROY_BACKING_STORE,
+        renderer_source);
+  if (monitor |= currently_monitored) {

[Nico, 2011/01/18 00:39:52]

Is this supposed to be != (it's currently |=)?

This makes stuff dcheck in Add() with tabpose on mac.

+    if (monitor) {
+      registrar_.Add(
+          this,
+          NotificationType::RENDER_WIDGET_HOST_WILL_DESTROY_BACKING_STORE,
+          renderer_source);
+      registrar_.Add(
+          this,
+          NotificationType::RENDER_WIDGET_HOST_DID_UPDATE_BACKING_STORE,
+          renderer_source);
+      registrar_.Add(
+          this,
+          NotificationType::RENDER_WIDGET_HOST_DID_RECEIVE_PAINT_AT_SIZE_ACK,
+          renderer_source);
+    } else {
+      registrar_.Remove(
+          this,
+          NotificationType::RENDER_WIDGET_HOST_WILL_DESTROY_BACKING_STORE,
+          renderer_source);
+      registrar_.Remove(
+          this,
+          NotificationType::RENDER_WIDGET_HOST_DID_UPDATE_BACKING_STORE,
+          renderer_source);
+      registrar_.Remove(
+          this,
+          NotificationType::RENDER_WIDGET_HOST_DID_RECEIVE_PAINT_AT_SIZE_ACK,
+          renderer_source);
+    }
+  }
+}
+
 void ThumbnailGenerator::AskForSnapshot(RenderWidgetHost* renderer,
                                         bool prefer_backing_store,
                                         ThumbnailReadyCallback* callback,
@@ -356,7 +395,7 @@ void ThumbnailGenerator::Observe(NotificationType type,
     case NotificationType::RENDER_VIEW_HOST_CREATED_FOR_TAB: {
       // Install our observer for all new RVHs.
       RenderViewHost* renderer = Details<RenderViewHost>(details).ptr();
-      renderer->set_painting_observer(this);
+      MonitorRenderer(renderer, true);
       break;
     }
 
@@ -371,6 +410,26 @@ void ThumbnailGenerator::Observe(NotificationType type,
       WidgetDestroyed(Source<RenderWidgetHost>(source).ptr());
       break;
 
+    case NotificationType::RENDER_WIDGET_HOST_WILL_DESTROY_BACKING_STORE:
+      WidgetWillDestroyBackingStore(
+          Source<RenderWidgetHost>(source).ptr(),
+          Details<BackingStore>(details).ptr());
+      break;
+
+    case NotificationType::RENDER_WIDGET_HOST_DID_UPDATE_BACKING_STORE:
+      WidgetDidUpdateBackingStore(Source<RenderWidgetHost>(source).ptr());
+      break;
+
+    case NotificationType::RENDER_WIDGET_HOST_DID_RECEIVE_PAINT_AT_SIZE_ACK: {
+      RenderWidgetHost::PaintAtSizeAckDetails* size_ack_details =
+          Details<RenderWidgetHost::PaintAtSizeAckDetails>(details).ptr();
+      WidgetDidReceivePaintAtSizeAck(
+          Source<RenderWidgetHost>(source).ptr(),
+          size_ack_details->tag,
+          size_ack_details->size);
+      break;
+    }
+
     case NotificationType::TAB_CONTENTS_DISCONNECTED:
       TabContentsDisconnected(Source<TabContents>(source).ptr());
       break;