Use WebViewHelper::LocalMainFrame where possible.

third_party/WebKit/Source/web/tests/VisualViewportTest.cpp

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "core/frame/VisualViewport.h"
 
 #include <memory>
 
 #include "core/dom/Document.h"
 #include "core/frame/BrowserControls.h"
@@ skipping 141 matching lines @@
   }
 
   void RegisterMockedHttpURLLoad(const std::string& url,
                                  const std::string& fileName) {
     URLTestHelpers::RegisterMockedURLLoad(
         ToKURL(url),
         blink::testing::WebTestDataPath(WebString::FromUTF8(fileName)));
   }
 
   WebViewBase* WebViewImpl() const { return helper_.WebView(); }
-  LocalFrame* GetFrame() const {
-    return helper_.WebView()->MainFrameImpl()->GetFrame();
-  }
+  LocalFrame* GetFrame() const { return helper_.LocalMainFrame()->GetFrame(); }
 
   static void ConfigureSettings(WebSettings* settings) {
     settings->SetJavaScriptEnabled(true);
     settings->SetPreferCompositingToLCDTextEnabled(true);
   }
 
   static void ConfigureAndroidSettings(WebSettings* settings) {
     ConfigureSettings(settings);
     settings->SetViewportEnabled(true);
     settings->SetViewportMetaEnabled(true);
@@ skipping 2247 matching lines @@
                                    "    margin: 0px;"
                                    "  }"
                                    "  div { height:110vh; width: 110vw; }"
                                    "</style>"
                                    "<div></div>",
                                    base_url);
 }
 
 }  // namespace
 }  // namespace blink