Remove usages of WebContents::GetRenderViewHost().

This CL was uploaded by git cl split.

R=jwd@chromium.org

Bug: 1142671
Change-Id: I9501b09c902d0741f7bbd92d1ada0ff06bfa5136
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2500609
Auto-Submit: Lucas Gadani <lfg@chromium.org>
Reviewed-by: Jesse Doherty <jwd@chromium.org>
Commit-Queue: Jesse Doherty <jwd@chromium.org>
Cr-Commit-Position: refs/heads/master@{#821270}

chrome/browser/metrics/desktop_session_duration/desktop_session_duration_observer.cc

@@ -14,7 +14,7 @@ DesktopSessionDurationObserver::DesktopSessionDurationObserver(
     content::WebContents* web_contents,
     DesktopSessionDurationTracker* service)
     : content::WebContentsObserver(web_contents), service_(service) {
-  RegisterInputEventObserver(web_contents->GetRenderViewHost());
+  RegisterInputEventObserver(web_contents->GetMainFrame()->GetRenderViewHost());
 }
 
 DesktopSessionDurationObserver::~DesktopSessionDurationObserver() {}

chrome/browser/metrics/metrics_memory_details.cc

@@ -208,7 +208,7 @@ void MetricsMemoryDetails::UpdateSiteIsolationMetrics() {
 
     // If this is a RVH for a subframe; skip it to avoid double-counting the
     // WebContents.
-    if (rvh != contents->GetRenderViewHost())
+    if (rvh != contents->GetMainFrame()->GetRenderViewHost())
       continue;
 
     // The rest of this block will happen only once per WebContents.