Update {virtual,override} to follow C++11 style in ppapi.

ppapi/nacl_irt/manifest_service.cc

Index: ppapi/nacl_irt/manifest_service.cc
diff --git a/ppapi/nacl_irt/manifest_service.cc b/ppapi/nacl_irt/manifest_service.cc
index cc5a2678551ad639eeab354ced3cf9be740372b6..a97c5d42d02c10e88160e26045c63bc0b0556436 100644
--- a/ppapi/nacl_irt/manifest_service.cc
+++ b/ppapi/nacl_irt/manifest_service.cc
@@ -33,7 +33,7 @@ class ManifestMessageFilter : public IPC::SyncMessageFilter {
             true /* manual_reset */, false /* initially_signaled */) {
   }
 
-  virtual bool Send(IPC::Message* message) override {
+  bool Send(IPC::Message* message) override {
     // Wait until set up is actually done.
     connected_event_.Wait();
     return SyncMessageFilter::Send(message);
@@ -41,19 +41,19 @@ class ManifestMessageFilter : public IPC::SyncMessageFilter {
 
   // When set up is done, OnFilterAdded is called on IO thread. Unblocks the
   // Send().
-  virtual void OnFilterAdded(IPC::Sender* sender) override {
+  void OnFilterAdded(IPC::Sender* sender) override {
     SyncMessageFilter::OnFilterAdded(sender);
     connected_event_.Signal();
   }
 
   // If an error is found, unblocks the Send(), too, to return an error.
-  virtual void OnChannelError() override {
+  void OnChannelError() override {
     SyncMessageFilter::OnChannelError();
     connected_event_.Signal();
   }
 
   // Similar to OnChannelError, unblocks the Send() on the channel closing.
-  virtual void OnChannelClosing() override {
+  void OnChannelClosing() override {
     SyncMessageFilter::OnChannelClosing();
     connected_event_.Signal();
   }