mandoline: Add back/forward support and UI.

components/web_view/url_request_cloneable.cc

+// Copyright 2015 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 "components/web_view/url_request_cloneable.h"
+
+#include "base/logging.h"
+#include "mojo/common/data_pipe_utils.h"
+
+namespace web_view {
+
+URLRequestCloneable::URLRequestCloneable(mojo::URLRequestPtr original_request)
+    : url_(original_request->url),
+      method_(original_request->method),
+      headers_(original_request->headers.Pass()),
+      response_body_buffer_size_(original_request->response_body_buffer_size),
+      auto_follow_redirects_(original_request->auto_follow_redirects),
+      bypass_cache_(original_request->bypass_cache),
+      body_(original_request->body.size()) {

[sky, 2015/09/08 16:00:32]

I believe this force body_ to non-null, even if original_request->body is null.
I suspect we don't want that.

+  // TODO(erg): Maybe we can do some sort of async copy here?
+  for (size_t i = 0; i < original_request->body.size(); ++i) {
+    mojo::common::BlockingCopyToString(original_request->body[i].Pass(),
+                                       &body_[i]);
+  }
+}
+
+URLRequestCloneable::~URLRequestCloneable() {}
+
+mojo::URLRequestPtr URLRequestCloneable::Clone() const {
+  mojo::URLRequestPtr request = mojo::URLRequest::New();
+  request->url = url_;
+  request->method = method_;
+  request->headers = headers_.Clone();
+  request->response_body_buffer_size = response_body_buffer_size_;
+  request->auto_follow_redirects = auto_follow_redirects_;
+  request->bypass_cache = bypass_cache_;
+
+  for (const std::string& body_data : body_) {
+    uint32_t num_bytes = body_data.size();
+    MojoCreateDataPipeOptions options;
+    options.struct_size = sizeof(MojoCreateDataPipeOptions);
+    options.flags = MOJO_CREATE_DATA_PIPE_OPTIONS_FLAG_NONE;
+    options.element_num_bytes = 1;
+    options.capacity_num_bytes = num_bytes;
+    mojo::DataPipe data_pipe(options);
+    request->body.push_back(data_pipe.consumer_handle.Pass());
+    WriteDataRaw(data_pipe.producer_handle.get(),
+                 body_data.data(),
+                 &num_bytes,
+                 MOJO_WRITE_DATA_FLAG_ALL_OR_NONE);
+    DCHECK_EQ(num_bytes, body_data.size());
+  }
+
+  return request.Pass();
+}
+
+}  // namespace web_view