Move enable extensions define to a build flag.

chrome/renderer/chrome_render_view_observer.h

 // Copyright (c) 2012 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.
 
 #ifndef CHROME_RENDERER_CHROME_RENDER_VIEW_OBSERVER_H_
 #define CHROME_RENDERER_CHROME_RENDER_VIEW_OBSERVER_H_
 
 #include <set>
 #include <string>
 #include <vector>
 
 #include "base/macros.h"
 #include "base/timer/timer.h"
 #include "build/build_config.h"
 #include "content/public/common/browser_controls_state.h"
 #include "content/public/renderer/render_view_observer.h"
+#include "extensions/features/features.h"
 #include "url/gurl.h"
 
 class ContentSettingsObserver;
 class SkBitmap;
 
 namespace blink {
 class WebView;
 struct WebWindowFeatures;
 }
 
@@ skipping 15 matching lines @@
   // RenderViewObserver implementation.
   bool OnMessageReceived(const IPC::Message& message) override;
   void DidCommitProvisionalLoad(blink::WebLocalFrame* frame,
                                 bool is_new_navigation) override;
   void Navigate(const GURL& url) override;
   void OnDestruct() override;
 
 #if !defined(OS_ANDROID)
   void OnWebUIJavaScript(const base::string16& javascript);
 #endif
-#if defined(ENABLE_EXTENSIONS)
+#if BUILDFLAG(ENABLE_EXTENSIONS)
   void OnSetVisuallyDeemphasized(bool deemphasized);
 #endif
 #if defined(OS_ANDROID)
   void OnUpdateBrowserControlsState(content::BrowserControlsState constraints,
                                     content::BrowserControlsState current,
                                     bool animate);
 #endif
   void OnGetWebApplicationInfo();
   void OnSetWindowFeatures(const blink::WebWindowFeatures& window_features);
 
   // Determines if a host is in the strict security host set.
   bool IsStrictSecurityHost(const std::string& host);
 
   // Save the JavaScript to preload if a ViewMsg_WebUIJavaScript is received.
   std::vector<base::string16> webui_javascript_;
 
   // Owned by ChromeContentRendererClient and outlive us.
   web_cache::WebCacheImpl* web_cache_impl_;
 
   // true if webview is overlayed with grey color.
   bool webview_visually_deemphasized_;
 
   DISALLOW_COPY_AND_ASSIGN(ChromeRenderViewObserver);
 };
 
 #endif  // CHROME_RENDERER_CHROME_RENDER_VIEW_OBSERVER_H_