[reland] Browser Side Text Input State Tracking for OOPIF (Aura Only)

content/browser/renderer_host/render_widget_host_view_base.h

 // 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.
 
 #ifndef CONTENT_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_VIEW_BASE_H_
 #define CONTENT_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_VIEW_BASE_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include <memory>
 #include <string>
 #include <vector>
 
 #include "base/callback_forward.h"
 #include "base/macros.h"
 #include "base/observer_list.h"
 #include "base/process/kill.h"
 #include "base/timer/timer.h"
 #include "build/build_config.h"
 #include "cc/output/compositor_frame.h"
 #include "cc/surfaces/surface_id.h"
 #include "content/browser/renderer_host/event_with_latency_info.h"
+#include "content/browser/renderer_host/text_input_manager.h"
 #include "content/common/content_export.h"
 #include "content/common/input/input_event_ack_state.h"
 #include "content/public/browser/readback_types.h"
 #include "content/public/browser/render_widget_host_view.h"
 #include "ipc/ipc_listener.h"
 #include "third_party/WebKit/public/platform/modules/screen_orientation/WebScreenOrientationType.h"
 #include "third_party/WebKit/public/web/WebPopupType.h"
 #include "third_party/WebKit/public/web/WebTextDirection.h"
 #include "ui/base/ime/text_input_mode.h"
 #include "ui/base/ime/text_input_type.h"
@@ skipping 25 matching lines @@
 namespace ui {
 class LatencyInfo;
 }
 
 namespace content {
 class BrowserAccessibilityDelegate;
 class BrowserAccessibilityManager;
 class RenderWidgetHostViewBaseObserver;
 class SyntheticGesture;
 class SyntheticGestureTarget;
+class TextInputManager;
 class WebCursor;
 struct DidOverscrollParams;
 struct NativeWebKeyboardEvent;
 struct TextInputState;
 
 // Basic implementation shared by concrete RenderWidgetHostView subclasses.
-class CONTENT_EXPORT RenderWidgetHostViewBase : public RenderWidgetHostView,
-                                                public IPC::Listener {
+class CONTENT_EXPORT RenderWidgetHostViewBase
+    : public RenderWidgetHostView,
+      public IPC::Listener,
+      public TextInputManager::Observer {
  public:
   ~RenderWidgetHostViewBase() override;
 
   float current_device_scale_factor() const {
     return current_device_scale_factor_;
   }
 
   // RenderWidgetHostView implementation.
   void SetBackgroundColor(SkColor color) override;
   void SetBackgroundColorToDefault() final;
@@ skipping 146 matching lines @@
   // embedded within the RenderWidgetHostViewBase's Surface to the
   // coordinate space of the embedding Surface. Typically this means that a
   // point was received from an out-of-process iframe's RenderWidget and needs
   // to be translated to viewport coordinates for the root RWHV, in which case
   // this method is called on the root RWHV with the out-of-process iframe's
   // SurfaceId.
   virtual void TransformPointToLocalCoordSpace(const gfx::Point& point,
                                                cc::SurfaceId original_surface,
                                                gfx::Point* transformed_point);
 
+  // Updates the state of the input method attached to the view.
+  virtual void TextInputStateChanged(const TextInputState& text_input_state);
+
   //----------------------------------------------------------------------------
   // The following static methods are implemented by each platform.
 
   static void GetDefaultScreenInfo(blink::WebScreenInfo* results);
 
   //----------------------------------------------------------------------------
   // The following pure virtual methods are implemented by derived classes.
 
   // Perform all the initialization steps necessary for this object to represent
   // a popup (such as a <select> dropdown), then shows the popup at |pos|.
   virtual void InitAsPopup(RenderWidgetHostView* parent_host_view,
                            const gfx::Rect& bounds) = 0;
 
   // Perform all the initialization steps necessary for this object to represent
   // a full screen window.
   // |reference_host_view| is the view associated with the creating page that
   // helps to position the full screen widget on the correct monitor.
   virtual void InitAsFullscreen(RenderWidgetHostView* reference_host_view) = 0;
 
   // Sets the cursor to the one associated with the specified cursor_type
   virtual void UpdateCursor(const WebCursor& cursor) = 0;
 
   // Indicates whether the page has finished loading.
   virtual void SetIsLoading(bool is_loading) = 0;
 
-  // Updates the state of the input method attached to the view.
-  virtual void TextInputStateChanged(const TextInputState& params) = 0;
-
   // Cancel the ongoing composition of the input method attached to the view.
   virtual void ImeCancelComposition() = 0;
 
   // Notifies the View that the renderer has ceased to exist.
   virtual void RenderProcessGone(base::TerminationStatus status,
                                  int error_code) = 0;
 
   // Tells the View to destroy itself.
   virtual void Destroy() = 0;
 
@@ skipping 83 matching lines @@
   virtual void LockCompositingSurface() = 0;
   virtual void UnlockCompositingSurface() = 0;
 
   // Updates the range of the marked text in an IME composition.
   virtual void ImeCompositionRangeChanged(
       const gfx::Range& range,
       const std::vector<gfx::Rect>& character_bounds) = 0;
 
   // Add and remove observers for lifetime event notifications. The order in
   // which notifications are sent to observers is undefined. Clients must be
   // sure to remove the observer before they go away.

[Charlie Reis, 2016/05/18 20:46:04]

Maybe you can add a similar comment to the add/remove observer methods in
TextInputManager?

[EhsanK, 2016/05/24 20:42:44]

Done.

   void AddObserver(RenderWidgetHostViewBaseObserver* observer);
   void RemoveObserver(RenderWidgetHostViewBaseObserver* observer);
 
   // Exposed for testing.
   virtual bool IsChildFrameForTesting() const;
   virtual cc::SurfaceId SurfaceIdForTesting() const;
 
+  // TextInputManager::Observer implementation.
+  void OnDestroyingTextInputManager(
+      TextInputManager* text_input_manager) override;

[Charlie Reis, 2016/05/18 20:46:04]

nit: This belongs near the top, under "IPC::Listener implementation."

[EhsanK, 2016/05/24 20:42:45]

Done. This is removed from this class since RenderWidgetHostViewBase is no
longer an observer of TextInputManager (breaking the observer loop as suggested
in your comment on line 24 of "text_input_manager.h").

[Charlie Reis, 2016/05/26 06:22:03]

Thanks, though that isn't what my line 24 comment was about.  I wanted to avoid
having TextInputManager observe RWHV, which is the other direction.

+
  protected:
   // Interface class only, do not construct.
   RenderWidgetHostViewBase();
 
   void NotifyObserversAboutShutdown();
 
+  // Returns a reference to the current instance of TextInputManager. If no
+  // no reference is found, this method tries to obtain one from the

[Charlie Reis, 2016/05/18 20:46:04]

nit: "no no"

[EhsanK, 2016/05/24 20:42:44]

Done.

+  // RenderWidgetHostDelegate. Returns nullptr if no reference exists or
+  // can be obtained. Unless not possible, this method should be used internally

[Charlie Reis, 2016/05/18 20:46:04]

I don't follow the "Unless not possible" part.  Is there a case when it can't be
used?  (You can also rephrase by ending the sentence with "when possible," which
would flow a little better, though I'm still curious about when it wouldn't be.)

[EhsanK, 2016/05/24 20:42:45]

What I meant to say is that, we should always use GetTextInputManager() since it
tries to initialize everything upon the first call. Basically,
|text_input_manager_| is nullptr at first.

However, in RWHVAura we need to dereference |text_input_manager_| in some const
methods. GetTextInputManager() cannot be const, unless we make it and then
initialize |text_input_manager_| by const casting |this|; which would seem
weird.

+  // to obtain TextInputManager.
+  TextInputManager* GetTextInputManager();
+
   // Whether this view is a popup and what kind of popup it is (select,
   // autofill...).
   blink::WebPopupType popup_type_;
 
   // The background color of the web content.
   SkColor background_color_;
 
   // While the mouse is locked, the cursor is hidden from the user. Mouse events
   // are still generated. However, the position they report is the last known
   // mouse position just as mouse lock was entered; the movement they report
   // indicates what the change in position of the mouse would be had it not been
   // locked.
   bool mouse_locked_;
 
   // Whether we are showing a context menu.
   bool showing_context_menu_;
 
   // A buffer containing the text inside and around the current selection range.
   base::string16 selection_text_;
 
   // The offset of the text stored in |selection_text_| relative to the start of
   // the web page.
   size_t selection_text_offset_;
 
   // The current selection range relative to the start of the web page.
   gfx::Range selection_range_;
 
- protected:
   // The scale factor of the display the renderer is currently on.
   float current_device_scale_factor_;
 
   // The orientation of the display the renderer is currently on.
   display::Display::Rotation current_display_rotation_;
 
   // Whether pinch-to-zoom should be enabled and pinch events forwarded to the
   // renderer.
   bool pinch_zoom_enabled_;
 
+  // A reference to current TextInputManager instance this RWHV is registered
+  // with. This is initially nullptr until the first time the view calls
+  // GetTextInputManager(). It can also become nullptr if the top-level
+  // RenderWidgetHostDelegate owning the TextInputManager is destroyed.
+  TextInputManager* text_input_manager_;
+
  private:
   void FlushInput();
 
   gfx::Rect current_display_area_;
 
   uint32_t renderer_frame_number_;
 
   base::OneShotTimer flush_input_timer_;
 
   base::ObserverList<RenderWidgetHostViewBaseObserver> observers_;
 
   base::WeakPtrFactory<RenderWidgetHostViewBase> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(RenderWidgetHostViewBase);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_VIEW_BASE_H_