Remove usages of WebContents::GetRenderViewHost().

This CL was uploaded by git cl split.

R=ksakamoto@chromium.org

Bug: 1142671
Change-Id: I58ff750aed0569b77cac8e1001fa1672437eb1e4
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2501127
Auto-Submit: Lucas Gadani <lfg@chromium.org>
Reviewed-by: Kunihiko Sakamoto <ksakamoto@chromium.org>
Commit-Queue: Kunihiko Sakamoto <ksakamoto@chromium.org>
Cr-Commit-Position: refs/heads/master@{#821072}

content/browser/web_package/signed_exchange_request_handler_browsertest.cc

@@ -332,8 +332,11 @@ class SignedExchangeRequestHandlerBrowserTest
 
   void WaitUntilSXGIsCached(const GURL& url) {
     scoped_refptr<PrefetchedSignedExchangeCache> cache =
-        static_cast<RenderFrameHostImpl*>(
-            shell()->web_contents()->GetRenderViewHost()->GetMainFrame())
+        static_cast<RenderFrameHostImpl*>(shell()
+                                              ->web_contents()
+                                              ->GetMainFrame()
+                                              ->GetRenderViewHost()
+                                              ->GetMainFrame())
             ->EnsurePrefetchedSignedExchangeCache();
 
     if (cache->GetExchanges().find(url) != cache->GetExchanges().end())

content/browser/web_package/signed_exchange_subresource_prefetch_browsertest.cc

@@ -63,7 +63,8 @@ std::string GetHeaderIntegrityString(const net::SHA256HashValue& hash) {
 }
 
 PrefetchedSignedExchangeCache::EntryMap GetCachedExchanges(Shell* shell) {
-  RenderViewHost* rvh = shell->web_contents()->GetRenderViewHost();
+  RenderViewHost* rvh =
+      shell->web_contents()->GetMainFrame()->GetRenderViewHost();
   RenderFrameHostImpl* rfh =
       static_cast<RenderFrameHostImpl*>(rvh->GetMainFrame());
   scoped_refptr<PrefetchedSignedExchangeCache> cache =