Get rid of base::SharedMemory::NULLHandle();

content/renderer/renderer_blink_platform_impl.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/renderer/renderer_blink_platform_impl.h"
 
 #include <memory>
 #include <utility>
 
 #include "base/command_line.h"
@@ skipping 531 matching lines @@
   uint32_t font_data_size;
   FontDescriptor src_font_descriptor(src_font);
   base::SharedMemoryHandle font_data;
   if (!RenderThread::Get()->Send(new RenderProcessHostMsg_LoadFont(
         src_font_descriptor, &font_data_size, &font_data, font_id))) {
     *out = NULL;
     *font_id = 0;
     return false;
   }
 
-  if (font_data_size == 0 || font_data == base::SharedMemory::NULLHandle() ||
-      *font_id == 0) {
+  if (font_data_size == 0 || !font_data.IsValid() || *font_id == 0) {
     LOG(ERROR) << "Bad response from RenderProcessHostMsg_LoadFont() for " <<
         src_font_descriptor.font_name;
     *out = NULL;
     *font_id = 0;
     return false;
   }
 
   // TODO(jeremy): Need to call back into WebKit to make sure that the font
   // isn't already activated, based on the font id.  If it's already
   // activated, don't reactivate it here - crbug.com/72727 .
@@ skipping 727 matching lines @@
 //------------------------------------------------------------------------------
 void RendererBlinkPlatformImpl::RequestPurgeMemory() {
   // TODO(tasak|bashi): We should use ChildMemoryCoordinator here, but
   // ChildMemoryCoordinator isn't always available as it's only initialized
   // when kMemoryCoordinatorV0 is enabled.
   // Use ChildMemoryCoordinator when memory coordinator is always enabled.
   base::MemoryCoordinatorClientRegistry::GetInstance()->PurgeMemory();
 }
 
 }  // namespace content