mandoline: Add back/forward support and UI.

components/web_view/web_view_impl.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/web_view_impl.h"
 
 #include "base/command_line.h"
 #include "components/devtools_service/public/cpp/switches.h"
 #include "components/view_manager/public/cpp/scoped_view_ptr.h"
 #include "components/view_manager/public/cpp/view.h"
 #include "components/view_manager/public/cpp/view_tree_connection.h"
 #include "components/web_view/frame.h"
 #include "components/web_view/frame_connection.h"
 #include "components/web_view/frame_devtools_agent.h"
 #include "components/web_view/frame_tree.h"
 #include "components/web_view/pending_web_view_load.h"
+#include "components/web_view/url_request_cloneable.h"
 #include "mojo/application/public/cpp/application_impl.h"
 #include "mojo/converters/geometry/geometry_type_converters.h"
 #include "url/gurl.h"
 
 namespace web_view {
 namespace {
 
 bool EnableRemoteDebugging() {
   return base::CommandLine::ForCurrentProcess()->HasSwitch(
       devtools_service::kRemoteDebuggingPort);
 }
 
 }  // namespace
 
+using web_view::mojom::ButtonState;
+
 ////////////////////////////////////////////////////////////////////////////////
 // WebViewImpl, public:
 
 WebViewImpl::WebViewImpl(mojo::ApplicationImpl* app,
                          mojom::WebViewClientPtr client,
                          mojo::InterfaceRequest<mojom::WebView> request)
     : app_(app),
       client_(client.Pass()),
       binding_(this, request.Pass()),
       root_(nullptr),
@@ skipping 26 matching lines @@
     devtools_agent_->AttachFrame(forward_agent.Pass(), &client_properties);
   }
 
   FrameTreeClient* frame_tree_client = frame_connection->frame_tree_client();
   const uint32_t content_handler_id = frame_connection->GetContentHandlerID();
   frame_tree_.reset(new FrameTree(
       content_handler_id, content_, view_tree_client.Pass(), this,
       frame_tree_client, frame_connection.Pass(), client_properties));
 }
 
+void WebViewImpl::LoadRequestImpl(mojo::URLRequestPtr request) {
+  client_->BackForwardChanged(
+      back_list_.empty() ? ButtonState::BUTTON_STATE_DISABLED
+                         : ButtonState::BUTTON_STATE_ENABLED,
+      forward_list_.empty() ? ButtonState::BUTTON_STATE_DISABLED
+                            : ButtonState::BUTTON_STATE_ENABLED);
+
+  current_page_request_.reset(new URLRequestCloneable(request.Pass()));
+  pending_load_.reset(new PendingWebViewLoad(this));
+  pending_load_->Init(current_page_request_->Clone());
+}
+
 ////////////////////////////////////////////////////////////////////////////////
 // WebViewImpl, WebView implementation:
 
 void WebViewImpl::LoadRequest(mojo::URLRequestPtr request) {
-  pending_load_.reset(new PendingWebViewLoad(this));
-  pending_load_->Init(request.Pass());
+  // Clear the forward list when performing a top level load request.
+  forward_list_.clear();
+
+  if (current_page_request_) {
+    // TODO(erg): This doesn't deal with redirect chains. If you navigate to a
+    // site, and it 300s, we put both the url which caused the 300 and the
+    // target url here, when we should not add the redirect url to the back
+    // list.
+    back_list_.push_back(current_page_request_.Pass());
+  }
+
+  LoadRequestImpl(request.Pass());
 }
 
 void WebViewImpl::GetViewTreeClient(
     mojo::InterfaceRequest<mojo::ViewTreeClient> view_tree_client) {
   mojo::ViewTreeConnection::Create(this, view_tree_client.Pass());
 }
 
+void WebViewImpl::GoBack() {
+  if (back_list_.empty())
+    return;
+
+  // Take the current page request and put it in the forward list.
+  forward_list_.push_back(current_page_request_.Pass());
+
+  mojo::URLRequestPtr new_request = back_list_.back()->Clone();
+  back_list_.resize(back_list_.size() - 1);
+
+  LoadRequestImpl(new_request.Pass());
+}
+
+void WebViewImpl::GoForward() {
+  if (forward_list_.empty())
+    return;
+
+  back_list_.push_back(current_page_request_.Pass());
+
+  mojo::URLRequestPtr new_request = forward_list_.back()->Clone();
+  forward_list_.resize(forward_list_.size() - 1);
+
+  LoadRequestImpl(new_request.Pass());
+}
+
 ////////////////////////////////////////////////////////////////////////////////
 // WebViewImpl, mojo::ViewTreeDelegate implementation:
 
 void WebViewImpl::OnEmbed(mojo::View* root) {
   // We must have been granted embed root priviledges, otherwise we can't
   // Embed() in any descendants.
   DCHECK(root->connection()->IsEmbedRoot());
   root->AddObserver(this);
   root_ = root;
   content_ = root->connection()->CreateView();
@@ skipping 70 matching lines @@
 ////////////////////////////////////////////////////////////////////////////////
 // WebViewImpl, FrameDevToolsAgentDelegate implementation:
 
 void WebViewImpl::HandlePageNavigateRequest(const GURL& url) {
   mojo::URLRequestPtr request(mojo::URLRequest::New());
   request->url = url.spec();
   client_->TopLevelNavigate(request.Pass());
 }
 
 }  // namespace web_view