Extract minimal RenderViewHost interface for embedders, leaving

content/browser/renderer_host/backing_store_manager.cc

 // 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.
 
 #include "content/browser/renderer_host/backing_store_manager.h"
 
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/memory/mru_cache.h"
 #include "base/sys_info.h"
@@ skipping 127 matching lines @@
     // Limit the number of large backing stores (tabs) to the memory tier number
     // (between 2-5). While we allow a larger amount of memory for people who
     // have large windows, this means that those who use small browser windows
     // won't ever cache more than 5 tabs, so they pay a smaller memory cost.
     if (large_cache->size() >= MaxNumberOfBackingStores())
       ExpireLastBackingStore(large_cache);
     cache = large_cache;
   } else {
     cache = small_cache;
   }
-  BackingStore* backing_store = static_cast<RenderWidgetHostImpl*>(
-      host)->AllocBackingStore(backing_store_size);
+  BackingStore* backing_store =
+      RenderWidgetHostImpl::From(host)->AllocBackingStore(backing_store_size);
   if (backing_store)
     cache->Put(host, backing_store);
   return backing_store;
 }
 
 int ComputeTotalArea(const std::vector<gfx::Rect>& rects) {
   // We assume that the given rects are non-overlapping, which is a property of
   // the paint rects generated by the PaintAggregator.
 #ifndef NDEBUG
   for (size_t i = 0; i < rects.size(); ++i) {
@@ skipping 49 matching lines @@
         !(backing_store = CreateBackingStore(host, backing_store_size))) {
       DCHECK(needs_full_paint != NULL);
       *needs_full_paint = true;
       *scheduled_completion_callback = false;
       // Makes no sense to paint the transport dib if we are going
       // to request a full paint.
       return;
     }
   }
 
-  backing_store->PaintToBackingStore(host->process(), bitmap,
+  backing_store->PaintToBackingStore(host->GetProcess(), bitmap,
                                      bitmap_rect, copy_rects,
                                      completion_callback,
                                      scheduled_completion_callback);
 }
 
 // static
 BackingStore* BackingStoreManager::Lookup(RenderWidgetHost* host) {
   if (large_cache) {
     BackingStoreCache::iterator it = large_cache->Get(host);
     if (it != large_cache->end())
@@ skipping 39 matching lines @@
   size_t mem = 0;
   BackingStoreCache::iterator it;
   for (it = large_cache->begin(); it != large_cache->end(); ++it)
     mem += it->second->MemorySize();
 
   for (it = small_cache->begin(); it != small_cache->end(); ++it)
     mem += it->second->MemorySize();
 
   return mem;
 }