Remove usages of WebContents::GetRenderViewHost().

This CL was uploaded by git cl split.

R=corising@chromium.org

Bug: 1142671
Change-Id: I63425a4accecedcffa4da3e746a0ccf449296336
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2500611
Auto-Submit: Lucas Gadani <lfg@chromium.org>
Reviewed-by: Caroline Rising <corising@chromium.org>
Commit-Queue: Caroline Rising <corising@chromium.org>
Cr-Commit-Position: refs/heads/master@{#821263}

chrome/browser/ui/views/find_bar_host.cc

@@ -116,7 +116,8 @@ bool FindBarHost::MaybeForwardKeyEventToWebpage(
   // input. Otherwise Up and Down arrow key strokes get eaten. "Nom Nom Nom".
   contents->ClearFocusedElement();
   NativeWebKeyboardEvent event(key_event);
-  contents->GetRenderViewHost()
+  contents->GetMainFrame()
+      ->GetRenderViewHost()
       ->GetWidget()
       ->ForwardKeyboardEventWithLatencyInfo(event, *key_event.latency());
   return true;