Make code path for bounds changes getting to renderer less brittle

content/browser/web_contents/web_contents_view_aura.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/browser/web_contents/web_contents_view_aura.h"
 
 #include "base/auto_reset.h"
 #include "base/command_line.h"
 #include "base/metrics/histogram.h"
 #include "base/strings/utf_string_conversions.h"
@@ skipping 25 matching lines @@
 #include "content/public/common/content_switches.h"
 #include "content/public/common/drop_data.h"
 #include "net/base/net_util.h"
 #include "third_party/WebKit/public/web/WebInputEvent.h"
 #include "ui/aura/client/aura_constants.h"
 #include "ui/aura/client/drag_drop_client.h"
 #include "ui/aura/client/drag_drop_delegate.h"
 #include "ui/aura/client/window_tree_client.h"
 #include "ui/aura/env.h"
 #include "ui/aura/root_window.h"
-#include "ui/aura/root_window_observer.h"
 #include "ui/aura/window.h"
-#include "ui/aura/window_observer.h"
 #include "ui/base/clipboard/clipboard.h"
 #include "ui/base/clipboard/custom_data_helper.h"
 #include "ui/base/dragdrop/drag_drop_types.h"
 #include "ui/base/dragdrop/drag_utils.h"
 #include "ui/base/dragdrop/drop_target_event.h"
 #include "ui/base/dragdrop/os_exchange_data.h"
 #include "ui/base/hit_test.h"
 #include "ui/compositor/layer.h"
 #include "ui/compositor/scoped_layer_animation_settings.h"
 #include "ui/events/event.h"
@@ skipping 582 matching lines @@
   ImageLayerDelegate layer_delegate_;
 
   // During tests, the aura windows don't get any paint updates. So the overlay
   // container keeps waiting for a paint update it never receives, causing a
   // timeout. So during tests, disable the wait for paint updates.
   bool need_paint_update_;
 
   DISALLOW_COPY_AND_ASSIGN(OverscrollNavigationOverlay);
 };
 
-class WebContentsViewAura::WindowObserver
-    : public aura::WindowObserver, public aura::RootWindowObserver {
- public:
-  explicit WindowObserver(WebContentsViewAura* view)
-      : view_(view),
-        parent_(NULL) {
-    view_->window_->AddObserver(this);
-  }
-
-  virtual ~WindowObserver() {
-    view_->window_->RemoveObserver(this);
-    if (view_->window_->GetDispatcher())
-      view_->window_->GetDispatcher()->RemoveRootWindowObserver(this);
-    if (parent_)
-      parent_->RemoveObserver(this);
-
-#if defined(OS_WIN)
-    if (parent_) {
-      const aura::Window::Windows& children = parent_->children();
-      for (size_t i = 0; i < children.size(); ++i)
-        children[i]->RemoveObserver(this);
-    }
-#endif
-  }
-
-  // Overridden from aura::WindowObserver:
-#if defined(OS_WIN)
-  // Constrained windows are added as children of the parent's parent's view

[rharrison, 2013/11/20 16:40:55]

jam, are the views that are of concern here being hard coded added as the
parent's parent's children or is it that they are actually the root view's
children and that happens to be the parent of the parent right now? Am I going
to have to make changes in other places for the NPAPI code since the NVHA CL I
am working on, https://codereview.chromium.org/48113013/, is going to add
another window to the hiearchy and that is going to break assumptions?

I am trying to figure out how to integrate this with my ancestor work at the
moment and I am not familiar with how the NPAPI code works.
I am thinking of three different sets of windows that could be the constrained
window set, can you clarify which is the correct one?

1) All children of windows about this up to the root, since they could
potentially overlap.
2) Just all children of the root window.
3) Children of the parent's parent, which is actually something different then
the root window.

-  // which may overlap with windowed NPAPI plugins. In that case, tell the RWHV
-  // so that it can update the plugins' cutout rects accordingly.
-  // Note: this is hard coding how Chrome layer adds its dialogs. Since NPAPI is
-  // going to be deprecated in a year, this is ok for now. The test for this is
-  // PrintPreviewTest.WindowedNPAPIPluginHidden.
-  virtual void OnWindowAdded(aura::Window* new_window) OVERRIDE {
-    if (new_window->parent() != parent_)
-      return;
-
-    new_window->AddObserver(this);
-    UpdateConstrainedWindows(NULL);
-  }
-
-  virtual void OnWillRemoveWindow(aura::Window* window) OVERRIDE {
-    if (window->parent() == parent_ && window != view_->window_) {
-      window->RemoveObserver(this);
-      UpdateConstrainedWindows(window);
-    }
-  }
-
-  virtual void OnWindowVisibilityChanged(aura::Window* window,
-                                         bool visible) OVERRIDE {
-    if (window->parent() == parent_ && window != view_->window_)
-      UpdateConstrainedWindows(NULL);
-  }
-#endif
-
-  virtual void OnWindowParentChanged(aura::Window* window,
-                                     aura::Window* parent) OVERRIDE {
-    if (window != view_->window_)
-      return;
-    if (parent_)
-      parent_->RemoveObserver(this);
-
-#if defined(OS_WIN)
-    if (parent_) {
-      const aura::Window::Windows& children = parent_->children();
-      for (size_t i = 0; i < children.size(); ++i)
-        children[i]->RemoveObserver(this);
-
-      RenderWidgetHostViewAura* view = ToRenderWidgetHostViewAura(
-          view_->web_contents_->GetRenderWidgetHostView());
-      if (view)
-        view->UpdateConstrainedWindowRects(std::vector<gfx::Rect>());
-    }
-#endif
-
-    parent_ = parent;
-    if (parent) {
-      parent->AddObserver(this);
-#if defined(OS_WIN)
-      const aura::Window::Windows& children = parent_->children();
-      for (size_t i = 0; i < children.size(); ++i) {
-        if (children[i] != view_->window_)
-          children[i]->AddObserver(this);
-      }
-#endif
-    }
-  }
-
-  virtual void OnWindowBoundsChanged(aura::Window* window,
-                                     const gfx::Rect& old_bounds,
-                                     const gfx::Rect& new_bounds) OVERRIDE {
-    if (window == parent_ || window == view_->window_) {
-      SendScreenRects();
-      if (view_->touch_editable_)
-        view_->touch_editable_->UpdateEditingController();
-#if defined(OS_WIN)
-    } else {
-      UpdateConstrainedWindows(NULL);
-#endif
-    }
-  }
-
-  virtual void OnWindowAddedToRootWindow(aura::Window* window) OVERRIDE {
-    if (window == view_->window_)
-      window->GetDispatcher()->AddRootWindowObserver(this);
-  }
-
-  virtual void OnWindowRemovingFromRootWindow(aura::Window* window) OVERRIDE {
-    if (window == view_->window_)
-      window->GetDispatcher()->RemoveRootWindowObserver(this);
-  }
-
-  // Overridden RootWindowObserver:
-  virtual void OnRootWindowHostMoved(const aura::RootWindow* root,
-                                     const gfx::Point& new_origin) OVERRIDE {
-    TRACE_EVENT1("ui",
-                 "WebContentsViewAura::WindowObserver::OnRootWindowHostMoved",
-                 "new_origin", new_origin.ToString());
-
-    // This is for the desktop case (i.e. Aura desktop).
-    SendScreenRects();
-  }
-
- private:
-  void SendScreenRects() {
-    RenderWidgetHostImpl::From(view_->web_contents_->GetRenderViewHost())->
-        SendScreenRects();
-  }
-
-#if defined(OS_WIN)
-  void UpdateConstrainedWindows(aura::Window* exclude) {
-    RenderWidgetHostViewAura* view = ToRenderWidgetHostViewAura(
-        view_->web_contents_->GetRenderWidgetHostView());
-    if (!view)
-      return;
-
-    std::vector<gfx::Rect> constrained_windows;
-    const aura::Window::Windows& children = parent_->children();
-    for (size_t i = 0; i < children.size(); ++i) {
-      if (children[i] != view_->window_ &&
-          children[i] != exclude &&
-          children[i]->IsVisible()) {
-        constrained_windows.push_back(children[i]->GetBoundsInRootWindow());
-      }
-    }
-
-    view->UpdateConstrainedWindowRects(constrained_windows);
-  }
-#endif
-
-  WebContentsViewAura* view_;
-
-  // We cache the old parent so that we can unregister when it's not the parent
-  // anymore.
-  aura::Window* parent_;
-
-  DISALLOW_COPY_AND_ASSIGN(WindowObserver);
-};
-
 ////////////////////////////////////////////////////////////////////////////////
 // WebContentsViewAura, public:
 
 WebContentsViewAura::WebContentsViewAura(
     WebContentsImpl* web_contents,
     WebContentsViewDelegate* delegate)
     : web_contents_(web_contents),
       delegate_(delegate),
       current_drag_op_(blink::WebDragOperationNone),
       drag_dest_delegate_(NULL),
       current_rvh_for_drag_(NULL),
       overscroll_change_brightness_(false),
       current_overscroll_gesture_(OVERSCROLL_NONE),
       completed_overscroll_gesture_(OVERSCROLL_NONE),
       touch_editable_(TouchEditableImplAura::Create()) {
 }
 
 ////////////////////////////////////////////////////////////////////////////////
 // WebContentsViewAura, private:
 
 WebContentsViewAura::~WebContentsViewAura() {
   if (!window_)
     return;
 
-  window_observer_.reset();
+  bounds_observer_.reset();
 
   // Window needs a valid delegate during its destructor, so we explicitly
   // delete it here.
   window_.reset();
 }
 
 void WebContentsViewAura::SetupOverlayWindowForTesting() {
   if (navigation_overlay_)
     navigation_overlay_->SetupForTesting();
 }
@@ skipping 310 matching lines @@
     // explicitly add this WebContentsViewAura to their tree after they create
     // us.
     if (root_window) {
       aura::client::ParentWindowWithContext(
           window_.get(), root_window, root_window->GetBoundsInScreen());
     }
   }
   window_->layer()->SetMasksToBounds(true);
   window_->SetName("WebContentsViewAura");
 
-  window_observer_.reset(new WindowObserver(this));
+  bounds_observer_.reset(new NativeViewScreenBoundsObserver(this,
+                                                            window_.get()));
+
+#if defined(OS_WIN)
+  constrained_observer_.reset(new ConstrainedWindowsObserver(this));
+#endif
 
   // delegate_->GetDragDestDelegate() creates a new delegate on every call.
   // Hence, we save a reference to it locally. Similar model is used on other
   // platforms as well.
   if (delegate_)
     drag_dest_delegate_ = delegate_->GetDragDestDelegate();
 }
 
 RenderWidgetHostView* WebContentsViewAura::CreateViewForWidget(
     RenderWidgetHost* render_widget_host) {
@@ skipping 464 matching lines @@
   web_contents_->GetRenderViewHost()->DragTargetDrop(
       event.location(),
       gfx::Screen::GetScreenFor(GetNativeView())->GetCursorScreenPoint(),
       ConvertAuraEventFlagsToWebInputEventModifiers(event.flags()));
   if (drag_dest_delegate_)
     drag_dest_delegate_->OnDrop();
   current_drop_data_.reset();
   return current_drag_op_;
 }
 
+////////////////////////////////////////////////////////////////////////////////
+// WebContentsViewAura, NativeViewScreenBoundsObserverDelegate implementation:
+
+void WebContentsViewAura::OnScreenPositionChanged() {
+  RenderWidgetHostImpl::From(web_contents_->GetRenderViewHost())->
+      SendScreenRects();
+}
+
+void WebContentsViewAura::OnScreenBoundsChanged() {
+  RenderWidgetHostImpl::From(web_contents_->GetRenderViewHost())->
+      SendScreenRects();
+  if (touch_editable_)
+    touch_editable_->UpdateEditingController();
+}
+
 }  // namespace content