Add mayHaveChangedRenderedSize callback.

content/renderer/render_view.cc

Index: content/renderer/render_view.cc
diff --git a/content/renderer/render_view.cc b/content/renderer/render_view.cc
index f7788e28394c546c85b4d89ba3f1c632265e105a..80d907ceaf495bd3471f0526dd98c99b10c470c6 100644
--- a/content/renderer/render_view.cc
+++ b/content/renderer/render_view.cc
@@ -2715,6 +2715,12 @@ void RenderView::didChangeContentsSize(WebFrame* frame, const WebSize& size) {
   CheckPreferredSize();
 }
 
+void RenderView::mayHaveChangedRenderedSize(WebFrame* frame) {
+  check_preferred_size_timer_.Stop();

[jamesr, 2011/05/24 20:31:25]

shouldn't this have the checks in CheckPreferredSize() (i.e.
send_preferred_size_changes_ && webview())?  Otherwise this is going to be
setting a _ton_ of timers

+  preferred_size_change_timer_.Start(TimeDelta::FromMilliseconds(10), this,
+                                     &RenderView::CheckPreferredSize);
+}
+
 void RenderView::CheckPreferredSize() {
   // We don't always want to send the change messages over IPC, only if we've
   // be put in that mode by getting a |ViewMsg_EnablePreferredSizeChangedMode|