Use WebViewHelper::LocalMainFrame where possible.

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

 // Copyright 2015 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 "modules/wake_lock/ScreenWakeLock.h"
 
 #include "core/dom/DOMImplementation.h"
 #include "core/dom/Document.h"
 #include "core/dom/DocumentInit.h"
 #include "core/frame/FrameTestHelpers.h"
@@ skipping 86 matching lines @@
   }
 
   void LoadFrame() {
     FrameTestHelpers::LoadFrame(web_view_helper_.WebView()->MainFrameImpl(),
                                 "http://example.com/foo.html");
     web_view_helper_.WebView()->UpdateAllLifecyclePhases();
   }
 
   LocalFrame* GetFrame() {
     DCHECK(web_view_helper_.WebView());
-    DCHECK(web_view_helper_.WebView()->MainFrameImpl());
-    return web_view_helper_.WebView()->MainFrameImpl()->GetFrame();
+    DCHECK(web_view_helper_.LocalMainFrame());
+    return web_view_helper_.LocalMainFrame()->GetFrame();
   }
 
   Screen* GetScreen() {
     DCHECK(GetFrame());
     DCHECK(GetFrame()->DomWindow());
     return GetFrame()->DomWindow()->screen();
   }
 
   bool ScreenKeepAwake() {
     DCHECK(GetScreen());
@@ skipping 88 matching lines @@
 
   SetKeepAwake(true);
   LoadFrame();
 
   EXPECT_FALSE(ScreenKeepAwake());
   EXPECT_FALSE(ClientKeepScreenAwake());
 }
 
 }  // namespace
 }  // namespace blink