Remove usages of WebContents::GetRenderViewHost().

This CL was uploaded by git cl split.

R=avi@chromium.org

Bug: 1142671
Change-Id: I5c57953a34cbab3cdafb0ce371a75297bfc7abde
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2500571
Auto-Submit: Lucas Gadani <lfg@chromium.org>
Reviewed-by: Avi Drissman <avi@chromium.org>
Commit-Queue: Avi Drissman <avi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#821084}

chrome/browser/ui/views/hung_renderer_view_browsertest.cc

@@ -43,9 +43,10 @@ class HungRendererDialogViewBrowserTest : public DialogBrowserTest {
   // DialogBrowserTest:
   void ShowUi(const std::string& name) override {
     auto* web_contents = browser()->tab_strip_model()->GetActiveWebContents();
-    HungRendererDialogView::Show(web_contents,
-                                 web_contents->GetRenderViewHost()->GetWidget(),
-                                 base::DoNothing::Repeatedly());
+    HungRendererDialogView::Show(
+        web_contents,
+        web_contents->GetMainFrame()->GetRenderViewHost()->GetWidget(),
+        base::DoNothing::Repeatedly());
 
     if (name == "MultiplePages") {
       auto* web_contents2 = chrome::DuplicateTabAt(browser(), 0);