blimp: Update page load status update indicator to use first paint.

blimp/engine/session/blimp_engine_session.h

 // 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.
 
 #ifndef BLIMP_ENGINE_SESSION_BLIMP_ENGINE_SESSION_H_
 #define BLIMP_ENGINE_SESSION_BLIMP_ENGINE_SESSION_H_
 
 #include <stdint.h>
 
 #include <memory>
 #include <vector>
 
 #include "base/macros.h"
 #include "blimp/common/proto/blimp_message.pb.h"
 #include "blimp/engine/feature/engine_render_widget_feature.h"
 #include "blimp/engine/feature/engine_settings_feature.h"
+#include "blimp/engine/session/page_load_tracker.h"
 #include "blimp/net/blimp_message_processor.h"
 #include "blimp/net/connection_error_observer.h"
 #include "content/public/browser/invalidate_type.h"
 #include "content/public/browser/web_contents_delegate.h"
 #include "content/public/browser/web_contents_observer.h"
 #include "net/base/completion_callback.h"
 #include "ui/base/ime/input_method_observer.h"
 #include "ui/gfx/geometry/size.h"
 
 namespace aura {
@@ skipping 38 matching lines @@
 class BlimpFocusClient;
 class BlimpScreen;
 class BlimpWindowTreeHost;
 class EngineNetworkComponents;
 
 class BlimpEngineSession
     : public BlimpMessageProcessor,
       public content::WebContentsDelegate,
       public content::WebContentsObserver,
       public ui::InputMethodObserver,
-      public EngineRenderWidgetFeature::RenderWidgetMessageDelegate {
+      public EngineRenderWidgetFeature::RenderWidgetMessageDelegate,
+      public PageLoadTrackerClient {
  public:
   using GetPortCallback = base::Callback<void(uint16_t)>;
 
   BlimpEngineSession(std::unique_ptr<BlimpBrowserContext> browser_context,
                      net::NetLog* net_log,
                      BlimpEngineConfig* config,
                      SettingsManager* settings_manager);
   ~BlimpEngineSession() override;
 
   // Starts the network stack on the IO thread, and sets default placeholder
@@ skipping 53 matching lines @@
   void RequestToLockMouse(content::WebContents* web_contents,
                           bool user_gesture,
                           bool last_unlocked_by_target) override;
   void CloseContents(content::WebContents* source) override;
   void ActivateContents(content::WebContents* contents) override;
   void ForwardCompositorProto(
       content::RenderWidgetHost* render_widget_host,
       const std::vector<uint8_t>& proto) override;
   void NavigationStateChanged(content::WebContents* source,
                               content::InvalidateTypes changed_flags) override;
-  void LoadProgressChanged(content::WebContents* source,
-                           double progress) override;
 
   // ui::InputMethodObserver overrides.
   void OnTextInputTypeChanged(const ui::TextInputClient* client) override;
   void OnFocus() override;
   void OnBlur() override;
   void OnCaretBoundsChanged(const ui::TextInputClient* client) override;
   void OnTextInputStateChanged(const ui::TextInputClient* client) override;
   void OnInputMethodDestroyed(const ui::InputMethod* input_method) override;
   void OnShowImeIfNeeded() override;
 
   // content::WebContentsObserver implementation.
   void RenderViewCreated(content::RenderViewHost* render_view_host) override;
   void RenderViewHostChanged(content::RenderViewHost* old_host,
                              content::RenderViewHost* new_host) override;
   void RenderViewDeleted(content::RenderViewHost* render_view_host) override;
 
+  // PageLoadTrackerClient implementation.
+  void SendPageLoadStatusUpdate(PageLoadStatus load_status) override;
+
   // Sets up and owns |new_contents|.
   void PlatformSetContents(std::unique_ptr<content::WebContents> new_contents);
 
-  // Stores the value of the last page load completed update sent to the client.
-  // This field is used per tab.
-  bool last_page_load_completed_value_;
-
   // Content BrowserContext for this session.
   std::unique_ptr<BlimpBrowserContext> browser_context_;
 
   // Engine configuration including assigned client token.
   BlimpEngineConfig* engine_config_;
 
   // Presents the client's single screen.
   std::unique_ptr<BlimpScreen> screen_;
 
   // Represents the (currently single) browser window into which tab(s) will
   // be rendered.
   std::unique_ptr<BlimpWindowTreeHost> window_tree_host_;
 
   // Used to apply standard focus conventions to the windows in the
   // WindowTreeHost hierarchy.
   std::unique_ptr<wm::FocusController> focus_client_;
 
   // Used to manage input capture.
   std::unique_ptr<aura::client::DefaultCaptureClient> capture_client_;
 
   // Used to attach null-parented windows (e.g. popups) to the root window.
   std::unique_ptr<aura::client::WindowTreeClient> window_tree_client_;
 
   // Only one web_contents is supported for blimp 0.5
   std::unique_ptr<content::WebContents> web_contents_;
 
+  // Tracks the page load status for a tab. Each PageLoadTracker is tied to a
+  // WebContents.
+  std::unique_ptr<PageLoadTracker> page_load_tracker_;

[Wez, 2016/05/25 03:33:10]

nit: You could re-use the tracker across multiple WebContents by calling
Observe() on it each time they change, if you want.

[Khushal, 2016/05/25 04:24:23]

The PageLoadTracker has state tied to a WebContents, I was worried swapping
would mean you start getting calls that don't respect the order it expects them
in. Seemed safer to just tie it to a WebContents forever.

[nasko, 2016/05/25 11:46:50]

+1 on having 1:1 objects instead of reuse. It is much easier to reason about and
less likely to make a mistake.

+
   // Manages all global settings for the engine session.
   SettingsManager* settings_manager_;
 
   // Handles all incoming messages for type SETTINGS.
   EngineSettingsFeature settings_feature_;
 
   // Handles all incoming and outgoing messages related to RenderWidget,
   // including INPUT, COMPOSITOR and RENDER_WIDGET messages.
   EngineRenderWidgetFeature render_widget_feature_;
 
   // Container for connection manager, authentication handler, and
   // browser connection handler. The components run on the I/O thread, and
   // this object is destroyed there.
   std::unique_ptr<EngineNetworkComponents> net_components_;
 
   std::unique_ptr<ThreadPipeManager> thread_pipe_manager_;
 
   // Used to send TAB_CONTROL or NAVIGATION messages to client.
   std::unique_ptr<BlimpMessageProcessor> tab_control_message_sender_;
   std::unique_ptr<BlimpMessageProcessor> navigation_message_sender_;
 
   DISALLOW_COPY_AND_ASSIGN(BlimpEngineSession);
 };
 
 }  // namespace engine
 }  // namespace blimp
 
 #endif  // BLIMP_ENGINE_SESSION_BLIMP_ENGINE_SESSION_H_