Revert of Revert of Migrate accessibility from RenderView to RenderFrame.

content/test/accessibility_browser_test_utils.cc

Index: content/test/accessibility_browser_test_utils.cc
diff --git a/content/test/accessibility_browser_test_utils.cc b/content/test/accessibility_browser_test_utils.cc
index ba0331c485fc84a0e910821e39473ee3d2dd3237..e91b2cf23987049983a4b10c74d2ac47ef17e215 100644
--- a/content/test/accessibility_browser_test_utils.cc
+++ b/content/test/accessibility_browser_test_utils.cc
@@ -8,8 +8,9 @@
 #include "base/logging.h"
 #include "base/strings/string_util.h"
 #include "base/strings/utf_string_conversions.h"
-#include "content/browser/renderer_host/render_view_host_impl.h"
+#include "content/browser/frame_host/render_frame_host_impl.h"
 #include "content/browser/renderer_host/render_widget_host_view_base.h"
+#include "content/browser/web_contents/web_contents_impl.h"
 #include "content/common/view_message_enums.h"
 #include "content/public/browser/web_contents.h"
 #include "content/public/common/url_constants.h"
@@ -26,9 +27,9 @@
       weak_factory_(this),
       event_target_id_(0) {
   WebContents* web_contents = shell_->web_contents();
-  view_host_ = static_cast<RenderViewHostImpl*>(
-      web_contents->GetRenderViewHost());
-  view_host_->SetAccessibilityCallbackForTesting(
+  frame_host_ = static_cast<RenderFrameHostImpl*>(
+      web_contents->GetMainFrame());
+  frame_host_->SetAccessibilityCallbackForTesting(
       base::Bind(&AccessibilityNotificationWaiter::OnAccessibilityEvent,
                  weak_factory_.GetWeakPtr()));
 }
@@ -42,13 +43,14 @@
       loop_runner_(new MessageLoopRunner()),
       weak_factory_(this),
       event_target_id_(0) {
-  WebContents* web_contents = shell_->web_contents();
-  view_host_ = static_cast<RenderViewHostImpl*>(
-      web_contents->GetRenderViewHost());
-  view_host_->SetAccessibilityCallbackForTesting(
+  WebContentsImpl* web_contents = static_cast<WebContentsImpl*>(
+      shell_->web_contents());
+  frame_host_ = static_cast<RenderFrameHostImpl*>(
+      web_contents->GetMainFrame());
+  frame_host_->SetAccessibilityCallbackForTesting(
       base::Bind(&AccessibilityNotificationWaiter::OnAccessibilityEvent,
                  weak_factory_.GetWeakPtr()));
-  view_host_->AddAccessibilityMode(accessibility_mode);
+  web_contents->AddAccessibilityMode(accessibility_mode);
 }
 
 AccessibilityNotificationWaiter::~AccessibilityNotificationWaiter() {
@@ -59,7 +61,7 @@
 }
 
 const ui::AXTree& AccessibilityNotificationWaiter::GetAXTree() const {
-  return view_host_->ax_tree_for_testing();
+  return *frame_host_->GetAXTreeForTesting();
 }
 
 void AccessibilityNotificationWaiter::OnAccessibilityEvent(