Remove usages of WebContents::GetRenderViewHost().

This CL was uploaded by git cl split.

R=benwells@chromium.org

Bug: 1142671
Change-Id: I17252ff848f20fc78acda5fc4bd589ada6314124
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2500487
Auto-Submit: Lucas Gadani <lfg@chromium.org>
Reviewed-by: Ben Wells <benwells@chromium.org>
Commit-Queue: Ben Wells <benwells@chromium.org>
Cr-Commit-Position: refs/heads/master@{#823057}

chrome/browser/external_protocol/external_protocol_handler_unittest.cc

@@ -189,8 +189,12 @@ class ExternalProtocolHandlerTest : public testing::Test {
     ExternalProtocolHandler::SetDelegateForTesting(&delegate_);
     delegate_.set_block_state(block_state);
     delegate_.set_os_state(os_state);
-    int process_id = web_contents_->GetRenderViewHost()->GetProcess()->GetID();
-    int routing_id = web_contents_->GetRenderViewHost()->GetRoutingID();
+    int process_id = web_contents_->GetMainFrame()
+                         ->GetRenderViewHost()
+                         ->GetProcess()
+                         ->GetID();
+    int routing_id =
+        web_contents_->GetMainFrame()->GetRenderViewHost()->GetRoutingID();
     ExternalProtocolHandler::LaunchUrl(url, process_id, routing_id,
                                        ui::PAGE_TRANSITION_LINK, true,
                                        initiating_origin);