Change other usages of .size() to .empty() when applicable.

chrome/renderer/webplugin_delegate_proxy.cc

 // 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.
 
 #include "chrome/renderer/webplugin_delegate_proxy.h"
 
 #if defined(TOOLKIT_USES_GTK)
 #include <gtk/gtk.h>
 #endif
 
@@ skipping 1323 matching lines @@
   // Blitting the bits directly is much faster than going through CG, and since
   // since the goal is just to move the raw pixels between two bitmaps with the
   // same pixel format (no compositing, color correction, etc.), it's safe.
   const size_t stride =
       skia::PlatformCanvas::StrideForWidth(plugin_rect_.width());
   const size_t chunk_size = 4 * rect.width();
   uint8* source_data = static_cast<uint8*>(transport_store_->memory()) +
                        rect.y() * stride + 4 * rect.x();
   // The two bitmaps are flipped relative to each other.
   int dest_starting_row = plugin_rect_.height() - rect.y() - 1;
-  DCHECK(backing_store_.size() > 0);
+  DCHECK(!backing_store_.empty());
   uint8* target_data = &(backing_store_[0]) + dest_starting_row * stride +
                        4 * rect.x();
   for (int row = 0; row < rect.height(); ++row) {
     memcpy(target_data, source_data, chunk_size);
     source_data += stride;
     target_data -= stride;
   }
 #else
   BlitCanvasToCanvas(backing_store_canvas_.get(), rect,
                      transport_store_canvas_.get(), rect.origin());
@@ skipping 230 matching lines @@
 }
 #endif
 
 void WebPluginDelegateProxy::OnURLRedirectResponse(bool allow,
                                                    int resource_id) {
   if (!plugin_)
     return;
 
   plugin_->URLRedirectResponse(allow, resource_id);
 }