Remove usages of WebContents::GetRenderViewHost().

This CL was uploaded by git cl split.

R=qinmin@chromium.org

Bug: 1142671
Change-Id: I352bace11acd570ae85530a978cc1b0e6853539c
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2500575
Auto-Submit: Lucas Gadani <lfg@chromium.org>
Reviewed-by: Min Qin <qinmin@chromium.org>
Commit-Queue: Min Qin <qinmin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#821123}

content/browser/download/download_browsertest.cc

@@ -3819,11 +3819,19 @@ IN_PROC_BROWSER_TEST_F(DownloadContentTest,
   mouse_event.button = blink::WebMouseEvent::Button::kLeft;
   mouse_event.SetPositionInWidget(15, 15);
   mouse_event.click_count = 1;
-  shell()->web_contents()->GetRenderViewHost()->GetWidget()->ForwardMouseEvent(
-      mouse_event);
+  shell()
+      ->web_contents()
+      ->GetMainFrame()
+      ->GetRenderViewHost()
+      ->GetWidget()
+      ->ForwardMouseEvent(mouse_event);
   mouse_event.SetType(blink::WebInputEvent::Type::kMouseUp);
-  shell()->web_contents()->GetRenderViewHost()->GetWidget()->ForwardMouseEvent(
-      mouse_event);
+  shell()
+      ->web_contents()
+      ->GetMainFrame()
+      ->GetRenderViewHost()
+      ->GetWidget()
+      ->ForwardMouseEvent(mouse_event);
 
   observer->WaitForFinished();
   EXPECT_EQ(

content/browser/download/save_package.cc

@@ -851,6 +851,7 @@ void SavePackage::SaveNextFile(bool process_all_remaining_items) {
         requester_frame->routing_id(), save_item_ptr->save_source(),
         save_item_ptr->full_path(), web_contents()->GetBrowserContext(),
         web_contents()
+            ->GetMainFrame()
             ->GetRenderViewHost()
             ->GetProcess()
             ->GetStoragePartition(),