Move handling of DraggableRegionsChanged notification from "view" to "frame".

third_party/WebKit/Source/core/frame/LocalFrameView.cpp

Index: third_party/WebKit/Source/core/frame/LocalFrameView.cpp
diff --git a/third_party/WebKit/Source/core/frame/LocalFrameView.cpp b/third_party/WebKit/Source/core/frame/LocalFrameView.cpp
index d73de59408045cbad62d330302496e7b8e58e166..fb94cbe84251313096d5bb1a512eccf5613edc2e 100644
--- a/third_party/WebKit/Source/core/frame/LocalFrameView.cpp
+++ b/third_party/WebKit/Source/core/frame/LocalFrameView.cpp
@@ -2822,8 +2822,11 @@ void LocalFrameView::UpdateDocumentAnnotatedRegions() const {
   if (new_regions == document->AnnotatedRegions())
     return;
   document->SetAnnotatedRegions(new_regions);
-  if (Page* page = frame_->GetPage())
-    page->GetChromeClient().AnnotatedRegionsChanged();
+
+  // Client should always be present, because this method cannot be called
+  // during detach (LocalFrame::Detach calls SetView(nullptr)).

[dcheng, 2017/06/08 20:02:56]

I would omit this comment: the precise details of this are likely to change over
time. I plan on documenting lifecycle things more thoroughly in a separate
README.md file.

[Łukasz Anforowicz, 2017/06/08 20:51:37]

Done.

+  DCHECK(frame_->Client());
+  frame_->Client()->AnnotatedRegionsChanged();
 }
 
 void LocalFrameView::DidAttachDocument() {