Remove PluginLoadObserver and related logic, it was only used for NPAPI.

content/child/npapi/plugin_stream_posix.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/child/npapi/plugin_stream.h"
-
-#include <string.h>
-
-#include "base/files/file_path.h"
-#include "base/files/file_util.h"
-#include "base/logging.h"
-#include "content/child/npapi/plugin_instance.h"
-
-namespace content {
-
-void PluginStream::ResetTempFileHandle() {
-  temp_file_ = NULL;
-}
-
-void PluginStream::ResetTempFileName() {
-  temp_file_path_ = base::FilePath();
-}
-
-void PluginStream::WriteAsFile() {
-  if (RequestedPluginModeIsAsFile())
-    instance_->NPP_StreamAsFile(&stream_, temp_file_path_.value().c_str());
-}
-
-size_t PluginStream::WriteBytes(const char* buf, size_t length) {
-  return fwrite(buf, sizeof(char), length, temp_file_);
-}
-
-bool PluginStream::OpenTempFile() {
-  DCHECK_EQ(static_cast<FILE*>(NULL), temp_file_);
-
-  if (base::CreateTemporaryFile(&temp_file_path_))
-    temp_file_ = base::OpenFile(temp_file_path_, "a");
-
-  if (!temp_file_) {
-    base::DeleteFile(temp_file_path_, false);
-    ResetTempFileName();
-    return false;
-  }
-  return true;
-}
-
-void PluginStream::CloseTempFile() {
-  if (!TempFileIsValid())
-    return;
-
-  base::CloseFile(temp_file_);
-  ResetTempFileHandle();
-}
-
-bool PluginStream::TempFileIsValid() const {
-  return temp_file_ != NULL;
-}
-
-}  // namespace content