Revert of Revert of Migrate accessibility from RenderView to RenderFrame.

content/browser/frame_host/interstitial_page_impl.cc

Index: content/browser/frame_host/interstitial_page_impl.cc
diff --git a/content/browser/frame_host/interstitial_page_impl.cc b/content/browser/frame_host/interstitial_page_impl.cc
index a4ea2997bf7700fc954a30fb699fe92f427b1852..1a1ed43dc658b6dad433ff43523c804bea6576e6 100644
--- a/content/browser/frame_host/interstitial_page_impl.cc
+++ b/content/browser/frame_host/interstitial_page_impl.cc
@@ -432,6 +432,13 @@
   controller_->delegate()->NotifyNavigationStateChanged(INVALIDATE_TYPE_TITLE);
 }
 
+AccessibilityMode InterstitialPageImpl::GetAccessibilityMode() const {
+  if (web_contents_)
+    return static_cast<WebContentsImpl*>(web_contents_)->GetAccessibilityMode();
+  else
+    return AccessibilityModeOff;
+}
+
 RenderViewHostDelegateView* InterstitialPageImpl::GetDelegateView() {
   return rvh_delegate_view_.get();
 }
@@ -533,7 +540,11 @@
 #if defined(OS_WIN)
 gfx::NativeViewAccessible
 InterstitialPageImpl::GetParentNativeViewAccessible() {
-  return render_widget_host_delegate_->GetParentNativeViewAccessible();
+  if (web_contents_) {
+    WebContentsImpl* wci = static_cast<WebContentsImpl*>(web_contents_);
+    return wci->GetParentNativeViewAccessible();
+  }
+  return NULL;
 }
 #endif