Revert 46842 - Reimplement accessibility of web content by caching the entire...

chrome/browser/renderer_host/render_widget_host_view_win.cc

Index: chrome/browser/renderer_host/render_widget_host_view_win.cc
===================================================================
--- chrome/browser/renderer_host/render_widget_host_view_win.cc	(revision 46846)
+++ chrome/browser/renderer_host/render_widget_host_view_win.cc	(working copy)
@@ -13,7 +13,6 @@
 #include "base/process_util.h"
 #include "base/thread.h"
 #include "base/win_util.h"
-#include "chrome/browser/browser_accessibility.h"
 #include "chrome/browser/browser_accessibility_manager.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/browser_trial.h"
@@ -27,7 +26,6 @@
 #include "chrome/common/chrome_constants.h"
 #include "chrome/common/chrome_switches.h"
 #include "chrome/common/native_web_keyboard_event.h"
-#include "chrome/common/notification_service.h"
 #include "chrome/common/plugin_messages.h"
 #include "chrome/common/render_messages.h"
 #include "gfx/canvas.h"
@@ -287,9 +285,6 @@
   renderer_accessible_ =
       CommandLine::ForCurrentProcess()->HasSwitch(
           switches::kEnableRendererAccessibility);
-  registrar_.Add(this,
-                 NotificationType::RENDERER_PROCESS_TERMINATED,
-                 NotificationService::AllSources());
 }
 
 RenderWidgetHostViewWin::~RenderWidgetHostViewWin() {
@@ -1477,64 +1472,40 @@
   return MA_ACTIVATE;
 }
 
-void RenderWidgetHostViewWin::UpdateAccessibilityTree(
-    const webkit_glue::WebAccessibility& tree) {
-  browser_accessibility_manager_.reset(
-      new BrowserAccessibilityManager(m_hWnd, tree));
-}
-
-void RenderWidgetHostViewWin::OnAccessibilityFocusChange(int acc_obj_id) {
-  if (browser_accessibility_manager_.get()) {
-    browser_accessibility_manager_->OnAccessibilityFocusChange(acc_obj_id);
-  }
-}
-
-void RenderWidgetHostViewWin::OnAccessibilityObjectStateChange(int acc_obj_id) {
-  if (browser_accessibility_manager_.get()) {
-    browser_accessibility_manager_->OnAccessibilityObjectStateChange(
-        acc_obj_id);
-  }
-}
-
-void RenderWidgetHostViewWin::Observe(NotificationType type,
-                                      const NotificationSource& source,
-                                      const NotificationDetails& details) {
-  DCHECK(type == NotificationType::RENDERER_PROCESS_TERMINATED);
-
-  // Get the RenderProcessHost that posted this notification, and exit
-  // if it's not the one associated with this host view.
-  RenderProcessHost* render_process_host =
-      Source<RenderProcessHost>(source).ptr();
-  DCHECK(render_process_host);
-  if (!render_widget_host_ ||
-      render_process_host != render_widget_host_->process())
-    return;
-
-  // If it was our RenderProcessHost that posted the notification,
-  // clear the BrowserAccessibilityManager, because the renderer is
-  // dead and any accessibility information we have is now stale.
-  browser_accessibility_manager_.reset(NULL);
-}
-
 LRESULT RenderWidgetHostViewWin::OnGetObject(UINT message, WPARAM wparam,
                                              LPARAM lparam, BOOL& handled) {
-  // TODO(dmazzoni): http://crbug.com/25564 Disabling accessibility in the
+  LRESULT reference_result = static_cast<LRESULT>(0L);
+  // TODO(jcampan): http://b/issue?id=1432077 Disabling accessibility in the
   // renderer is a temporary work-around until that bug is fixed.
-  if (!renderer_accessible_) {
-    handled = false;
-    return static_cast<LRESULT>(0L);
-  }
+  if (!renderer_accessible_)
+    return reference_result;
 
-  if (lparam == OBJID_CLIENT && browser_accessibility_manager_.get()) {
-    BrowserAccessibility* root = browser_accessibility_manager_->GetRoot();
-    if (root) {
-      return LresultFromObject(IID_IAccessible, wparam,
-                               static_cast<IAccessible*>(root->NewReference()));
+  // Accessibility readers will send an OBJID_CLIENT message.
+  if (OBJID_CLIENT == lparam) {
+    // If our MSAA DOM root is already created, reuse that pointer. Otherwise,
+    // create a new one.
+    if (!browser_accessibility_root_) {
+      // Create a new instance of IAccessible. Root id is 1000, to avoid
+      // conflicts with the ids used by MSAA.
+      BrowserAccessibilityManager::GetInstance()->CreateAccessibilityInstance(
+          IID_IAccessible, 1000,
+          render_widget_host_->routing_id(),
+          render_widget_host_->process()->id(),
+          m_hWnd,
+          reinterpret_cast<void **>(browser_accessibility_root_.Receive()));
+
+      if (!browser_accessibility_root_) {
+        // No valid root found, return with failure.
+        return static_cast<LRESULT>(0L);
+      }
     }
-  }
 
-  handled = false;
-  return static_cast<LRESULT>(0L);
+    // Create a reference to BrowserAccessibility which MSAA will marshall to
+    // the client.
+    reference_result = LresultFromObject(IID_IAccessible, wparam,
+        static_cast<IAccessible*>(browser_accessibility_root_));
+  }
+  return reference_result;
 }
 
 void RenderWidgetHostViewWin::OnFinalMessage(HWND window) {