<webview> Implement clear http cache API.

components/web_cache/browser/web_cache_manager.h

 // Copyright (c) 2011 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.
 
 // This is the browser side of the cache manager, it tracks the activity of the
 // render processes and allocates available memory cache resources.
 
 #ifndef COMPONENTS_WEB_CACHE_BROWSER_WEB_CACHE_MANAGER_H_
 #define COMPONENTS_WEB_CACHE_BROWSER_WEB_CACHE_MANAGER_H_
 
@@ skipping 68 matching lines @@
 
   // The global limit on the number of bytes in all the in-memory caches.
   size_t global_size_limit() const { return global_size_limit_; }
 
   // Sets the global size limit, forcing a recalculation of cache allocations.
   void SetGlobalSizeLimit(size_t bytes);
 
   // Clears all in-memory caches.
   void ClearCache();
 
+  // Instantly clears renderer cache for a process.
+  void ClearCacheForProcess(int process_id);
+
   // Clears all in-memory caches when a tab is reloaded or the user navigates
   // to a different website.
   void ClearCacheOnNavigation();
 
   // content::NotificationObserver implementation:
   void Observe(int type,
                const content::NotificationSource& source,
                const content::NotificationDetails& details) override;
 
   // Gets the default global size limit.  This interrogates system metrics to
@@ skipping 133 matching lines @@
   content::NotificationRegistrar registrar_;
 
   base::WeakPtrFactory<WebCacheManager> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(WebCacheManager);
 };
 
 }  // namespace web_cache
 
 #endif  // COMPONENTS_WEB_CACHE_BROWSER_WEB_CACHE_MANAGER_H_