Instrument pepper plugin load failures.

content/common/pepper_plugin_list.cc

Index: content/common/pepper_plugin_list.cc
===================================================================
--- content/common/pepper_plugin_list.cc	(revision 239266)
+++ content/common/pepper_plugin_list.cc	(working copy)
@@ -56,7 +56,7 @@
 
   size_t plugins_to_register = modules.size();
   if (plugins_to_register > kMaxPluginsToRegisterFromCommandLine) {
-    DLOG(WARNING) << plugins_to_register << " pepper plugins registered from"
+    VLOG(1) << plugins_to_register << " pepper plugins registered from"
         << " command line which exceeds the limit (maximum "
         << kMaxPluginsToRegisterFromCommandLine << " plugins allowed)";
     plugins_to_register = kMaxPluginsToRegisterFromCommandLine;
@@ -66,7 +66,7 @@
     std::vector<std::string> parts;
     base::SplitString(modules[i], ';', &parts);
     if (parts.size() < 2) {
-      DLOG(ERROR) << "Required mime-type not found";
+      VLOG(1) << "Required mime-type not found";
       continue;
     }
 
@@ -89,7 +89,7 @@
       if (base::PathExists(plugin.path)) {
         skip_file_check_flags |= index_mask;
       } else {
-        DLOG(ERROR) << "Plugin doesn't exist:" << plugin.path.MaybeAsASCII();
+        VLOG(1) << "Plugin doesn't exist: " << plugin.path.MaybeAsASCII();
         continue;
       }
     }