Convert some non-debug logging on content/common to debug logging.

content/common/pepper_plugin_registry.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 "content/common/pepper_plugin_registry.h"
 
 #include "base/command_line.h"
 #include "base/file_util.h"
 #include "base/native_library.h"
 #include "base/string_split.h"
@@ skipping 117 matching lines @@
 
 // static
 void PepperPluginRegistry::PreloadModules() {
   std::vector<content::PepperPluginInfo> plugins;
   ComputeList(&plugins);
   for (size_t i = 0; i < plugins.size(); ++i) {
     if (!plugins[i].is_internal) {
       std::string error;
       base::NativeLibrary library = base::LoadNativeLibrary(plugins[i].path,
                                                             &error);
-      LOG_IF(WARNING, !library) << "Unable to load plugin "
-                                << plugins[i].path.value() << " "
-                                << error;
+      DLOG_IF(WARNING, !library) << "Unable to load plugin "
+                                 << plugins[i].path.value() << " "
+                                 << error;
+      (void)library;  // Prevent release-mode warning.
     }
   }
 }
 
 const content::PepperPluginInfo* PepperPluginRegistry::GetInfoForPlugin(
     const webkit::WebPluginInfo& info) {
   for (size_t i = 0; i < plugin_list_.size(); ++i) {
     if (info.path == plugin_list_[i].path)
       return &plugin_list_[i];
   }
@@ skipping 74 matching lines @@
       // Preload all external plugins we're not running out of process.
       if (!module->InitAsLibrary(current.path)) {
         DLOG(ERROR) << "Failed to load pepper module: " << current.path.value();
         continue;
       }
     }
     preloaded_modules_[current.path] = module;
   }
 }